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Mifepristone

Generic name: mifepristone systemic

Brand names: Mifeprex, Korlym

Boxed Warning

Bacterial infections (Mifeprex)

Serious and sometimes fatal infections and bleeding occur very rarely following spontaneous, surgical, and medical abortions, including following mifepristone use. No causal relationship between the use of mifepristone and misoprostol and these reactions has been established. Before prescribing mifepristone, inform the patient about the risk of these serious events. Ensure that the patient knows whom to call and what to do, including going to an emergency room, if none of the provided contacts are reachable, if she experiences sustained fever, severe abdominal pain, prolonged heavy bleeding, or syncope, or if she experiences abdominal pain or discomfort or general malaise (including weakness, nausea, vomiting, or diarrhea) more than 24 hours after taking misoprostol.

Patients with serious bacterial infections (eg, Clostridium sordelli) and sepsis can present without fever, bacteremia, or significant findings on pelvic examination following an abortion. Very rarely, deaths have been reported in patients who presented without fever, with or without abdominal pain, but with leukocytosis with a marked left shift, tachycardia, hemoconcentration, and general malaise. A high index of suspicion is needed to rule out serious infection and sepsis.

Bleeding (Mifeprex)

Prolonged heavy bleeding may be a sign of incomplete abortion or other complications, and prompt medical or surgical intervention may be needed. Advise patients to seek immediate medical attention if they experience prolonged heavy vaginal bleeding.

Distribution program (Mifeprex)

Because of the risks of serious complications (eg, bacterial infections, bleeding), mifepristone is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the Mifeprex REMS program.

Medication guide (Mifeprex)

Advise patients to take their Medication Guide with them if they visit an emergency room or another health care provider who did not prescribe mifepristone, so that provider will be aware that the patient is undergoing a medical abortion.

Termination of intrauterine pregnancy (Korlym)

Mifepristone is a potent antagonist of progesterone and cortisol via the progesterone and glucocorticoid (GR-II) receptors, respectively. The antiprogestational effects will result in the termination of pregnancy. Pregnancy must be excluded before the initiation of treatment with mifepristone and prevented during treatment and for 1 month after stopping treatment by the use of a nonhormonal, medically acceptable method of contraception unless the patient has had a surgical sterilization, in which case, no additional contraception is needed. Pregnancy must also be excluded if treatment is interrupted for more than 14 days in females of reproductive potential.

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Tablet, Oral:

Korlym: 300 mg [contains fd&c yellow #10 aluminum lake, fd&c yellow #6 aluminum lake]

Mifeprex: 200 mg [contains corn starch]

Generic: 200 mg

Pharmacology

Mechanism of Action

Mifepristone is a synthetic steroid. At low doses, it competitively binds to the intracellular progesterone receptor, blocking the effects of progesterone. When used for the termination of pregnancy, this leads to contraction-inducing activity in the myometrium. In the absence of progesterone, mifepristone acts as a partial progesterone agonist. At high doses used for the treatment of hyperglycemia in patients with Cushing’s syndrome, mifepristone blocks the effect of cortisol at the glucocorticoid receptor (antagonizes the effects of cortisol on glucose metabolism) while at the same time increasing circulating cortisol concentrations.

Pharmacokinetics/Pharmacodynamics

Absorption

Oral: Rapid

Metabolism

Hepatic via CYP3A4 to three metabolites (active)

Excretion

Feces (83%); urine (9%)

Time to Peak

Oral: 90 minutes; Range: Single dose: 1-2 hours, Multiple doses: 1-4 hours

Half-Life Elimination

Single dose: Terminal: 18 hours following a slower phase where 50% eliminated between 12-72 hours; Multiple doses (600 mg/day): 85 hours

Protein Binding

98% to albumin and α1-acid glycoprotein

Use: Labeled Indications

Korlym: To control hyperglycemia occurring secondary to hypercortisolism in adult patients with endogenous Cushing syndrome who have type 2 diabetes mellitus or glucose intolerance and who failed surgery or who are not surgical candidates.

Limitations of use: Should not be used in the treatment of patients with type 2 diabetes unless it is secondary to Cushing syndrome.

Mifeprex: Medical termination of intrauterine pregnancy through 70 days gestation, in combination with misoprostol.

Use: Off Label

Early pregnancy lossbyes

Data from a randomized study support the use of mifepristone in conjunction with misoprostol for the management of early pregnancy loss (<13 weeks gestation) Schreiber 2018.

Based on the American College of Obstetricians and Gynecologists (ACOG) Practice Bulletin for Early Pregnancy Loss, mifepristone (administered prior to misoprostol) within the first 12 6/7 weeks of gestation is effective and recommended for the medical management of early pregnancy loss. This combination may significantly increase efficacy compared to misoprostol alone and should be considered when mifepristone is available. Use may be considered in patients who do not want to undergo surgical evacuation and who do not show signs of an infection, hemorrhage, severe anemia, or bleeding disorders. Misoprostol alone is also an effective and alternative option ACOG 200 2018.

Contraindications

Hypersensitivity to mifepristone or any component of the formulation.

Korlym (additional contraindications): Concomitant use of lovastatin, simvastatin, or CYP3A substrates with a narrow therapeutic range (eg, cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinine, sirolimus, tacrolimus); concomitant use of systemic corticosteroids for life-saving purposes (eg, immunosuppression following organ transplant); women with a history of unexplained vaginal bleeding, or endometrial hyperplasia with atypia or endometrial carcinoma; pregnancy.

Mifeprex (additional contraindications): Hypersensitivity to misoprostol or other prostaglandins; chronic adrenal failure; porphyrias; hemorrhagic disorder or concurrent anticoagulant therapy; intrauterine device in place; ectopic pregnancy or undiagnosed adnexal mass; concurrent long-term corticosteroid therapy.

Dosage and Administration

Dosing: Adult

Hyperglycemia in patients with Cushing syndrome (Korlym): Oral: Initial dose: 300 mg once daily. Dose may be increased in 300 mg increments at intervals of ≥2 to 4 weeks based on tolerability and symptom control. Maximum dose: 1,200 mg once daily, not to exceed 20 mg/kg/day. If treatment is interrupted, reinitiate at 300 mg daily or a dose lower than the dose that caused the treatment to be stopped if interruption due to adverse reactions.

Dosage adjustment of Korlym in patients already being treated with strong CYP3A inhibitor therapy: Initial: 300 mg once daily; may increase dose as clinically indicated (maximum dose: 900 mg/day).

Dosage adjustment of Korlym in patients who require initiation of strong CYP3A inhibitor therapy:

If current dose is 300 mg/day: No dosage adjustment necessary.

If current dose is 600 mg/day: Reduce dose to 300 mg once daily; if clinically indicated may increase dose to a maximum of 600 mg once daily.

If current dose is 900 mg/day: Reduce dose to 600 mg once daily; if clinically indicated, may increase dose to a maximum of 900 mg once daily.

If current dose is 1,200 mg/day: Reduce dose to 900 mg once daily.

Termination of intrauterine pregnancy (Mifeprex): Oral: Treatment consists of 3 office visits by the patient.

Day 1 (mifepristone administration): 200 mg taken as a single dose.

Day 2 or 3 (misoprostol administration): Misoprostol 800 mcg buccally 24 to 48 hours after mifepristone administration. Dose is administered as two 200 mcg tablets in each cheek pouch, held in place for 30 minutes. Any remnants may be swallowed with water or other liquid. Note: Patient may need treatment for cramps or gastrointestinal symptoms at this time.

Day 7 to 14 (post-treatment exam): Patient must return to the health care provider ~7 to 14 days after administration of mifepristone to confirm that complete termination of pregnancy has occurred and to evaluate the degree of bleeding. If complete expulsion has not occurred, but the pregnancy is not ongoing, women may be treated with another dose of misoprostol 800 mcg buccally. Women who choose to use a repeat dose of misoprostol should have another follow-up visit with their healthcare provider in approximately 7 days to assess for complete termination. Surgical termination is recommended to manage treatment failures.

Termination of pregnancy (off-label dosing): Mifepristone 200 mg orally followed by misoprostol 800 mcg vaginally 24 to 48 hours later (ACOG 143 2014; FIGO 2011).

Early pregnancy loss (off-label use): Oral: Mifepristone 200 mg orally followed by a vaginal dose of misoprostol 24 hours later (ACOG 200 2018; Schreiber 2018).

Dosing: Geriatric

Hyperglycemia in patients with Cushing syndrome: Refer to adult dosing.

Administration

Hyperglycemia in patients with Cushing syndrome: Administer as a single daily dose with a meal. Tablets should be swallowed whole, not crushed, split, or chewed.

Termination of intrauterine pregnancy: Remove any intrauterine device before treatment with mifepristone begins. Administer mifepristone orally and misoprostol buccally. Administer day 1 mifepristone as a single oral dose under supervision of a certified prescriber. Provide patient with phone number and name of provider to call in case of questions or emergencies.

Storage

Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).

Mifepristone Images

Drug Interactions

Abemaciclib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Abemaciclib. Management: In patients taking abemaciclib at a dose of 200 mg or 150 mg twice daily, reduce the dose to 100 mg twice daily when combined with strong CYP3A4 inhibitors. In patients taking abemaciclib 100 mg twice daily, decrease the dose to 50 mg twice daily. Consider therapy modification

Acalabrutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Acalabrutinib. Avoid combination

Ado-Trastuzumab Emtansine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Ado-Trastuzumab Emtansine. Specifically, strong CYP3A4 inhibitors may increase concentrations of the cytotoxic DM1 component. Avoid combination

Alfuzosin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Alfuzosin. Avoid combination

Alitretinoin (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Alitretinoin (Systemic). Management: Consider reducing the alitretinoin dose to 10 mg when used together with strong CYP3A4 inhibitors. Monitor for increased alitretinoin effects/toxicities if combined with a strong CYP3A4 inhibitor. Consider therapy modification

Almotriptan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Almotriptan. Management: Limit initial almotriptan adult dose to 6.25 mg and maximum adult dose to 12.5 mg/24-hrs when used with a strong CYP3A4 inhibitor. Avoid concurrent use in patients with impaired hepatic or renal function. Consider therapy modification

Alosetron: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Alosetron. Monitor therapy

ALPRAZolam: CYP3A4 Inhibitors (Strong) may increase the serum concentration of ALPRAZolam. Management: Consider using an alternative agent that is less likely to interact. If combined, monitor for increased therapeutic/toxic effects of alprazolam if combined with a strong CYP3A4 inhibitor. Consider therapy modification

Androgens: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Exceptions: Danazol. Monitor therapy

Anticoagulants: MiFEPRIStone may enhance the adverse/toxic effect of Anticoagulants. Specifically, the risk of bleeding may be increased. Avoid combination

Antidiabetic Agents: May enhance the hypoglycemic effect of Hypoglycemia-Associated Agents. Monitor therapy

Aprepitant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Aprepitant. Avoid combination

ARIPiprazole: CYP3A4 Inhibitors (Strong) may increase the serum concentration of ARIPiprazole. Management: See full interaction monograph for details. Consider therapy modification

ARIPiprazole Lauroxil: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of ARIPiprazole Lauroxil. Management: Please refer to the full interaction monograph for details concerning the recommended dose adjustments. Consider therapy modification

Astemizole: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Astemizole. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination

Asunaprevir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Asunaprevir. Avoid combination

Avanafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Avanafil. Avoid combination

Avapritinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Avapritinib. Avoid combination

Avatrombopag: MiFEPRIStone may increase the serum concentration of Avatrombopag. Management: Management of this interaction varies based on avatrombopag indication. Dose adjustments are required for patients using avatrombopag for chronic immune thrombocytopenia. See monograph for details. Consider therapy modification

Axitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Axitinib. Management: Avoid concurrent use of axitinib with any strong CYP3A inhibitor whenever possible. If a strong CYP3A inhibitor must be used with axitinib, a 50% axitinib dose reduction is recommended. Consider therapy modification

Barnidipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Barnidipine. Avoid combination

Bedaquiline: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bedaquiline. Management: Limit duration of concurrent use of bedaquiline with CYP3A4 inhibitors to no more than 14 days, unless the benefit of continued use outweighs the possible risks. Monitor for toxic effects of bedaquiline. Exceptions discussed in separate monographs. Consider therapy modification

Benperidol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Benperidol. Monitor therapy

Betamethasone (Ophthalmic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Betamethasone (Ophthalmic). Monitor therapy

Bictegravir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bictegravir. Monitor therapy

Blonanserin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Blonanserin. Avoid combination

Bortezomib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bortezomib. Monitor therapy

Bosentan: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Bosentan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bosentan. Management: Concomitant use of both a CYP2C9 inhibitor and a CYP3A inhibitor or a single agent that inhibits both enzymes with bosentan is likely to cause a large increase in serum concentrations of bosentan and is not recommended. See monograph for details. Monitor therapy

Bosentan: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Bosentan. Management: Concomitant use of both a CYP2C9 inhibitor and a CYP3A inhibitor or a single agent that inhibits both enzymes with bosentan is likely to cause a large increase in serum concentrations of bosentan and is not recommended. See monograph for details. Monitor therapy

Bosutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bosutinib. Avoid combination

Brentuximab Vedotin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brentuximab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be increased. Monitor therapy

Brexpiprazole: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brexpiprazole. Management: Reduce brexpiprazole dose 50% with strong CYP3A4 inhibitors; reduce to 25% of usual if used with both a moderate CYP3A4 inhibitor and a CYP2D6 inhibitor in patients not being treated for MDD, or strong CYP3A4 inhibitor used in a CYP2D6 poor metabolizer. Consider therapy modification

Brigatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brigatinib. Management: Avoid concurrent use of brigatinib with strong CYP3A4 inhibitors when possible. If combination cannot be avoided, reduce the brigatinib dose by approximately 50%, rounding to the nearest tablet strength (ie, from 180 mg to 90 mg, or from 90 mg to 60 mg). Consider therapy modification

Brinzolamide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brinzolamide. Monitor therapy

Bromocriptine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bromocriptine. Avoid combination

Budesonide (Nasal): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Nasal). Monitor therapy

Budesonide (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Oral Inhalation). Monitor therapy

Budesonide (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Systemic). Avoid combination

Budesonide (Topical): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Topical). Management: Per US prescribing information, avoid this combination. Canadian product labeling does not recommend strict avoidance. If combined, monitor for excessive glucocorticoid effects as budesonide exposure may be increased. Consider therapy modification

BusPIRone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of BusPIRone. Management: Limit the buspirone dose to 2.5 mg daily and monitor patients for increased buspirone effects/toxicities if combined with strong CYP3A4 inhibitors. Consider therapy modification

Cabazitaxel: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cabazitaxel. Management: Concurrent use of cabazitaxel with strong inhibitors of CYP3A4 should be avoided when possible. If such a combination must be used, consider a 25% reduction in the cabazitaxel dose. Consider therapy modification

Cabozantinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cabozantinib. Management: Avoid use of a strong CYP3A4 inhibitor with cabozantinib if possible. If combined, cabozantinib dose adjustments are recommended and vary based on the cabozantinib product used and the indication for use. See monograph for details. Consider therapy modification

Calcifediol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Calcifediol. Monitor therapy

Cannabidiol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cannabidiol. Monitor therapy

Cannabis: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Cannabis. More specifically, tetrahydrocannabinol serum concentrations may be increased. Monitor therapy

Cannabis: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cannabis. More specifically, tetrahydrocannabinol and cannabidiol serum concentrations may be increased. Monitor therapy

Cariprazine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cariprazine. Management: Cariprazine dose reductions of 50% are required; specific recommended management varies slightly for those stable on cariprazine versus those just starting cariprazine. See prescribing information or full interaction monograph for details. Consider therapy modification

Carvedilol: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Carvedilol. Specifically, concentrations of the S-carvedilol enantiomer may be increased. Monitor therapy

Ceritinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ceritinib. Management: If such combinations cannot be avoided, the ceritinib dose should be reduced by approximately one-third (to the nearest 150 mg). Resume the prior ceritinib dose after cessation of the strong CYP3A4 inhibitor. Exceptions discussed in separate monographs. Consider therapy modification

Cilostazol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cilostazol. Management: Consider reducing the cilostazol dose to 50 mg twice daily in adult patients who are also receiving strong inhibitors of CYP3A4. Consider therapy modification

Cinacalcet: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cinacalcet. Monitor therapy

Clofazimine: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

CloZAPine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of CloZAPine. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Monitor therapy

Cobimetinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cobimetinib. Avoid combination

Codeine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Codeine. Monitor therapy

Colchicine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Colchicine. Management: Colchicine is contraindicated in patients with impaired renal or hepatic function who are also receiving a strong CYP3A4 inhibitor. In those with normal renal and hepatic function, reduce colchicine dose as directed. See full monograph for details. Consider therapy modification

Conivaptan: May increase the serum concentration of MiFEPRIStone. Management: Limit mifepristone adult dose, when used for treatment of hyperglycemia in Cushing's syndrome, to a maximum of 600 mg/day when combined with conivaptan. Monitor for increased mifepristone toxicity regardless of dose or indication. Consider therapy modification

Copanlisib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Copanlisib. Management: If concomitant use of copanlisib and strong CYP3A4 inhibitors cannot be avoided, reduce the copanlisib dose to 45 mg. Monitor patients for increased copanlisib effects/toxicities. Consider therapy modification

Corticosteroids (Orally Inhaled): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Corticosteroids (Orally Inhaled). Management: Orally inhaled fluticasone propionate with a strong CYP3A4 inhibitor is not recommended. Exceptions: Beclomethasone (Oral Inhalation); Triamcinolone (Systemic). Monitor therapy

Corticosteroids (Systemic): MiFEPRIStone may diminish the therapeutic effect of Corticosteroids (Systemic). MiFEPRIStone may increase the serum concentration of Corticosteroids (Systemic). Management: Avoid mifepristone in patients who require long-term corticosteroid treatment of serious illnesses or conditions (e.g., for immunosuppression following transplantation). Corticosteroid effects may be reduced by mifepristone treatment. Avoid combination

Crizotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Crizotinib. Management: Avoid concomitant use of crizotinib and strong CYP3A4 inhibitors whenever possible. If combined use cannot be avoided, decrease the crizotinib dose to 250 mg daily. Exceptions are discussed in separate monographs. Consider therapy modification

CycloSPORINE (Systemic): MiFEPRIStone may increase the serum concentration of CycloSPORINE (Systemic). Management: Avoid cyclosporine during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

CYP2B6 Substrates (High risk with Inhibitors): MiFEPRIStone may increase the serum concentration of CYP2B6 Substrates (High risk with Inhibitors). Monitor therapy

CYP2C9 Substrates (High risk with Inhibitors): MiFEPRIStone may increase the serum concentration of CYP2C9 Substrates (High risk with Inhibitors). Management: Use CYP2C9 substrates at the lowest recommended dose, and monitor closely for adverse effects, during and in the 2 weeks following mifepristone treatment. Consider therapy modification

CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

CYP3A4 Inducers (Strong): May decrease the serum concentration of MiFEPRIStone. Avoid combination

CYP3A4 Inhibitors (Moderate): May decrease the metabolism of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

CYP3A4 Inhibitors (Strong): May increase the serum concentration of MiFEPRIStone. Management: Limit mifepristone adult dose, when used for treatment of hyperglycemia in Cushing's syndrome, to a maximum of 900 mg/day when combined with a strong CYP3A4 inhibitor. Monitor for increased mifepristone toxicity regardless of dose or indication. Consider therapy modification

CYP3A4 Substrates (High risk with Inhibitors): MiFEPRIStone may increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Minimize doses of CYP3A4 substrates, and monitor for increased concentrations/toxicity, during and 2 weeks following treatment with mifepristone. Avoid cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus. Consider therapy modification

Dabrafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dabrafenib. Avoid combination

Daclatasvir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Daclatasvir. Management: Decrease the daclatasvir dose to 30 mg once daily if combined with a strong CYP3A4 inhibitor. No dose adjustment is needed when daclatasvir is used with darunavir/cobicistat. Consider therapy modification

Dapoxetine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dapoxetine. Avoid combination

Dasatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dasatinib. Management: This combination should be avoided if possible. If combined, dasatinib dose reductions are recommended. See full monograph for details. Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Consider therapy modification

Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Delamanid: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Delamanid. Management: Increase ECG monitoring frequency if delamanid is combined with strong CYP3A4 inhibitors due to the risk for QTc interval prolongation. Continue frequent ECG assessments throughout full delamanid treatment period. Exceptions discussed separately. Consider therapy modification

DexAMETHasone (Ophthalmic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of DexAMETHasone (Ophthalmic). Monitor therapy

Dexketoprofen: May diminish the therapeutic effect of MiFEPRIStone. Monitor therapy

Diclofenac (Systemic): CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Diclofenac (Systemic). Management: Consider using a reduced dose of diclofenac when used together with moderate CYP2C9 inhibitors. Arthrotec (diclofenac and misoprostol) prescribing information recommends a maximum dose of 50 mg twice daily. Consider therapy modification

Digoxin: MiFEPRIStone may increase the serum concentration of Digoxin. Management: Measure serum digoxin concentration 1-2 weeks following mifepristone initiation, and in accordance with normal clinical practice thereafter, adjusting dose as needed. Monitor therapy

Dihydroergotamine: MiFEPRIStone may increase the serum concentration of Dihydroergotamine. Management: Avoid dihydroergotamine during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

DOCEtaxel: CYP3A4 Inhibitors (Strong) may increase the serum concentration of DOCEtaxel. Management: Avoid the concomitant use of docetaxel and strong CYP3A4 inhibitors when possible. If combined use is unavoidable, consider a 50% docetaxel dose reduction and monitor for increased docetaxel toxicities. Consider therapy modification

Dofetilide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dofetilide. Monitor therapy

Domperidone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Domperidone. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination

Doxercalciferol: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Doxercalciferol. Monitor therapy

DOXOrubicin (Conventional): CYP3A4 Inhibitors (Strong) may increase the serum concentration of DOXOrubicin (Conventional). Management: Seek alternatives to strong CYP3A4 inhibitors in patients treated with doxorubicin whenever possible. One U.S. manufacturer (Pfizer Inc.) recommends that these combinations be avoided. Consider therapy modification

Dronabinol: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Dronabinol. Monitor therapy

Dronabinol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dronabinol. Monitor therapy

Dronedarone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dronedarone. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination

Drospirenone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Drospirenone. Management: Drospirenone use is contraindicated specifically when the strong CYP3A4 inhibitors atazanavir and cobicistat are administered concurrently. Caution should be used when drospirenone is coadministered with other strong CYP3A4 inhibitors. Consider therapy modification

Dutasteride: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dutasteride. Monitor therapy

Duvelisib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Duvelisib. Management: Reduce the dose of duvelisib to 15 mg twice a day when used together with a strong CYP3A4 inhibitor. Consider therapy modification

Elagolix: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Elagolix. Management: Use of the elagolix 200 mg twice daily dose with a strong CYP3A4 inhibitor for longer than 1 month is not recommended. Limit combined use of the elagolix 150 mg once daily dose with a strong CYP3A4 inhibitor to a maximum of 6 months. Consider therapy modification

Eletriptan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eletriptan. Avoid combination

Elexacaftor, Tezacaftor, and Ivacaftor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Elexacaftor, Tezacaftor, and Ivacaftor. Management: When combined with strong CYP3A4 inhibitors, administer two elexacaftor/tezacaftor/ivacaftor tablets (100 mg/50 mg/75 mg) in the morning, twice a week, approximately 3 to 4 days apart. No evening doses of ivacaftor (150 mg) alone should be administered. Consider therapy modification

Eliglustat: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eliglustat. Management: Use should be avoided under some circumstances. See full drug interaction monograph for details. Consider therapy modification

Encorafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Encorafenib. Management: Avoid concomitant use of encorafenib and strong CYP3A4 inhibitors whenever possible. If concomitant administration is unavoidable, decrease the encorafenib dose. See monograph for details. Consider therapy modification

Enfortumab Vedotin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Enfortumab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be increased. Monitor therapy

Entrectinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Entrectinib. Management: Avoid strong CYP3A4 inhibitors during treatment with entrectinib. Reduce dose to 100 mg/day if combination cannot be avoided in adults and those 12 yrs of age or older with a BSA of at least 1.5 square meters. No alternative dosing provided for others. Consider therapy modification

Eplerenone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eplerenone. Avoid combination

Erdafitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Erdafitinib. Management: Avoid concomitant use of erdafitinib and strong CYP3A4 inhibitors when possible. If combined, monitor closely for erdafitinib adverse reactions and consider dose modifications accordingly. Consider therapy modification

Ergotamine: MiFEPRIStone may increase the serum concentration of Ergotamine. Management: Avoid ergotamine during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Erlotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Erlotinib. Management: Avoid use of this combination when possible. When the combination must be used, monitor the patient closely for the development of severe adverse reactions, and if such severe reactions occur, reduce the erlotinib dose (in 50 mg decrements). Consider therapy modification

Estrogen Derivatives: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Estrogen Derivatives. Monitor therapy

Estrogen Derivatives (Contraceptive): MiFEPRIStone may diminish the therapeutic effect of Estrogen Derivatives (Contraceptive). MiFEPRIStone may increase the serum concentration of Estrogen Derivatives (Contraceptive). Management: Women of childbearing potential should use an effective, nonhormonal means of contraception during and 4 weeks following mifepristone treatment. Consider therapy modification

Eszopiclone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eszopiclone. Management: Limit the eszopiclone dose to 2 mg daily when combined with strong CYP3A4 inhibitors and monitor for increased eszopiclone effects and toxicities (eg, somnolence, drowsiness, CNS depression). Consider therapy modification

Etizolam: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Etizolam. Management: Consider use of lower etizolam doses when using this combination; specific recommendations concerning dose adjustment are not available. Monitor clinical response to the combination closely. Consider therapy modification

Everolimus: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Everolimus. Avoid combination

Evogliptin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Evogliptin. Monitor therapy

Fedratinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fedratinib. Management: Consider alternatives when possible. If used together, decrease fedratinib dose to 200 mg/day. After the inhibitor is stopped, increase fedratinib to 300 mg/day for the first 2 weeks and then to 400 mg/day as tolerated. Consider therapy modification

FentaNYL: MiFEPRIStone may increase the serum concentration of FentaNYL. Management: Avoid fentanyl during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Fesoterodine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Fesoterodine. Management: Avoid fesoterodine doses greater than 4 mg daily in adult patients who are also receiving strong CYP3A4 inhibitors. Consider therapy modification

Flibanserin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Flibanserin. Avoid combination

Fluticasone (Nasal): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fluticasone (Nasal). Avoid combination

Fluticasone (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fluticasone (Oral Inhalation). Management: Use of orally inhaled fluticasone propionate with strong CYP3A4 inhibitors is not recommended. Use of orally inhaled fluticasone furoate with strong CYP3A4 inhibitors should be done with caution. Monitor patients using such a combination more closely. Consider therapy modification

Fluvastatin: MiFEPRIStone may increase the serum concentration of Fluvastatin. Management: Use fluvastatin at the lowest recommended dose, and monitor closely for adverse effects (including myopathy), during and in the 2 weeks following mifepristone treatment. Consider therapy modification

Fosamprenavir: May increase the serum concentration of MiFEPRIStone. Management: Limit mifepristone adult dose, when used for treatment of hyperglycemia in Cushing's syndrome, to a maximum of 600 mg/day when combined with fosamprenavir. Monitor for increased mifepristone toxicity regardless of dose or indication. Consider therapy modification

Fosaprepitant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fosaprepitant. Avoid combination

Fosnetupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fostamatinib: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Fostamatinib. Monitor therapy

Fusidic Acid (Systemic): May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Galantamine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Galantamine. Monitor therapy

Gilteritinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Gilteritinib. Management: Consider alternatives to the use of a strong CYP3A4 inhibitor with gilteritinib. If the combination cannot be avoided, monitor more closely for evidence of gilteritinib toxicities. Consider therapy modification

Glasdegib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Glasdegib. Management: Consider alternatives to this combination when possible. If the combination must be used, monitor closely for evidence of QT interval prolongation and other adverse reactions to glasdegib. Consider therapy modification

Grapefruit Juice: May increase the serum concentration of MiFEPRIStone. Monitor therapy

GuanFACINE: CYP3A4 Inhibitors (Strong) may increase the serum concentration of GuanFACINE. Management: Reduce the guanfacine dose by 50% when initiating this combination. Consider therapy modification

Halofantrine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Halofantrine. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination

Herbs (Hypoglycemic Properties): May enhance the hypoglycemic effect of Hypoglycemia-Associated Agents. Monitor therapy

Hypoglycemia-Associated Agents: May enhance the hypoglycemic effect of other Hypoglycemia-Associated Agents. Monitor therapy

Ibrutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ibrutinib. Management: Avoid concomitant use of ibrutinib and strong CYP3A4 inhibitors. If a strong CYP3A4 inhibitor must be used short-term (eg, anti-infectives for 7 days or less), interrupt ibrutinib therapy until the strong CYP3A4 inhibitor is discontinued. Avoid combination

Idelalisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Ifosfamide: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Ifosfamide. Monitor therapy

Iloperidone: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Iloperidone. Specifically, concentrations of the metabolites P88 and P95 may be increased. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Iloperidone. Management: Reduce iloperidone dose by half when administered with a strong CYP3A4 inhibitor. Consider therapy modification

Imatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Imatinib. Monitor therapy

Imidafenacin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Imidafenacin. Monitor therapy

Irinotecan Products: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Irinotecan Products. Specifically, serum concentrations of SN-38 may be increased. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Irinotecan Products. Avoid combination

Isavuconazonium Sulfate: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Isavuconazonium Sulfate. Specifically, CYP3A4 Inhibitors (Strong) may increase isavuconazole serum concentrations. Management: Combined use is considered contraindicated per US labeling. Lopinavir/ritonavir (and possibly other uses of ritonavir doses less than 400 mg every 12 hours) is treated as a possible exception to this contraindication despite strongly inhibiting CYP3A4. Avoid combination

Istradefylline: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Istradefylline. Management: Limit the maximum istradefylline dose to 20 mg daily when combined with strong CYP3A4 inhibitors and monitor for increased istradefylline effects/toxicities. Consider therapy modification

Ivabradine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ivabradine. Avoid combination

Ivacaftor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ivacaftor. Management: Ivacaftor dose reductions are required; consult full monograph content for age- and weight-specific recommendations. Consider therapy modification

Ivosidenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ivosidenib. Management: Avoid use of a strong CYP3A4 inhibitor with ivosidenib whenever possible. When combined use is required, reduce the ivosidenib dose to 250 mg once daily. Drugs listed as exceptions are discussed in further detail in separate drug interaction monographs. Consider therapy modification

Ixabepilone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ixabepilone. Consider therapy modification

Lacosamide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lacosamide. Monitor therapy

Lapatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lapatinib. Management: If an overlap in therapy cannot be avoided, consider reducing lapatinib adult dose to 500 mg/day during, and within 1 week of completing, treatment with the strong CYP3A4 inhibitor. Avoid combination

Larotrectinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Larotrectinib. Management: Avoid use of strong CYP3A4 inhibitors with larotrectinib. If this combination cannot be avoided, reduce the larotrectinib dose by 50%. Increase to previous dose after stopping the inhibitor after a period of 3 to 5 times the inhibitor half-life. Consider therapy modification

Lefamulin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lefamulin. Management: Avoid concomitant use of lefamulin tablets and strong inhibitors of CYP3A4. Avoid combination

Lemborexant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lemborexant. Avoid combination

Lercanidipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lercanidipine. Avoid combination

Levamlodipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Levamlodipine. Monitor therapy

Levobupivacaine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Levobupivacaine. Monitor therapy

Levomilnacipran: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Levomilnacipran. Management: Do not exceed a maximum adult levomilnacipran dose of 80 mg/day in patients also receiving strong CYP3A4 inhibitors. Consider therapy modification

Lomitapide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lomitapide. Avoid combination

Lorlatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lorlatinib. Management: Avoid use of lorlatinib with strong CYP3A4 inhibitors. If the combination cannot be avoided, reduce the lorlatinib dose from 100 mg once daily to 75 mg once daily, or from 75 mg once daily to 50 mg once daily. Consider therapy modification

Lorlatinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Avoid concurrent use of lorlatinib with any CYP3A4 substrates for which a minimal decrease in serum concentrations of the CYP3A4 substrate could lead to therapeutic failure and serious clinical consequences. Consider therapy modification

Lornoxicam: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Lornoxicam. Monitor therapy

Lovastatin: MiFEPRIStone may increase the serum concentration of Lovastatin. Management: Avoid lovastatin during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Lumateperone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lumateperone. Avoid combination

Lumefantrine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lumefantrine. Monitor therapy

Lurasidone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lurasidone. Avoid combination

Macitentan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Macitentan. Avoid combination

Maitake: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Manidipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Manidipine. Management: Consider avoiding concomitant use of manidipine and strong CYP3A4 inhibitors. If combined, monitor closely for increased manidipine effects and toxicities. Manidipine dose reductions may be required. Consider therapy modification

Maraviroc: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Maraviroc. Management: Reduce the adult dose of maraviroc to 150 mg twice daily when used with a strong CYP3A4 inhibitor. Do not use maraviroc with strong CYP3A4 inhibitors in patients with Clcr less than 30 mL/min. Consider therapy modification

Meperidine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Meperidine. Monitor therapy

Midostaurin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Midostaurin. Management: Seek alternatives to the concomitant use of midostaurin and strong CYP3A4 inhibitors if possible. If concomitant use cannot be avoided, monitor patients for increased risk of adverse reactions. Exceptions are discussed in separate monographs. Consider therapy modification

Mirodenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Mirodenafil. Management: Consider using a lower dose of mirodenafil when used with strong CYP3A4 inhibitors. Monitor for increased mirodenafil effects/toxicities with the use of this combination. Consider therapy modification

Monoamine Oxidase Inhibitors: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Naldemedine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Naldemedine. Monitor therapy

Nalfurafine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Nalfurafine. Monitor therapy

Naloxegol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Naloxegol. Avoid combination

Neratinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Neratinib. Avoid combination

Netupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Nilotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Nilotinib. Management: Avoid if possible. If combination needed, decrease nilotinib to 300 mg once/day for patients with resistant or intolerant Ph+ CML or to 200 mg once/day for patients with newly diagnosed Ph+ CML in chronic phase. Exceptions discussed in separate monograph. Consider therapy modification

NiMODipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of NiMODipine. Avoid combination

Nisoldipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Nisoldipine. Avoid combination

Olaparib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Olaparib. Management: Avoid use of strong CYP3A4 inhibitors in patients being treated with olaparib, if possible. If such concurrent use cannot be avoided, the dose of olaparib should be reduced to 100 mg twice daily. Consider therapy modification

Ospemifene: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ospemifene. Monitor therapy

Oxybutynin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Oxybutynin. Monitor therapy

OxyCODONE: CYP3A4 Inhibitors (Strong) may enhance the adverse/toxic effect of OxyCODONE. CYP3A4 Inhibitors (Strong) may increase the serum concentration of OxyCODONE. Serum concentrations of the active metabolite oxymorphone may also be increased. Consider therapy modification

Palbociclib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Palbociclib. Avoid combination

Panobinostat: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Panobinostat. Management: Reduce the panobinostat dose to 10 mg when it must be used with a strong CYP3A4 inhibitor. Consider therapy modification

Parecoxib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Parecoxib. Monitor therapy

Paricalcitol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Paricalcitol. Monitor therapy

PAZOPanib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of PAZOPanib. Management: Avoid concurrent use of pazopanib with strong inhibitors of CYP3A4 whenever possible. If it is not possible to avoid such a combination, reduce pazopanib adult dose to 400 mg. Further dose reductions may also be required. Consider therapy modification

Pegvisomant: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Pexidartinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Pexidartinib. Management: Avoid use of pexidartinib with strong CYP3A4 inhibitors if possible. If combined use cannot be avoided, the pexidartinib dose should be reduced. Decrease 800 mg or 600 mg daily doses to 200 mg twice daily. Decrease doses of 400 mg/day to 200 mg/day. Consider therapy modification

Phenylbutazone: May diminish the therapeutic effect of MiFEPRIStone. Management: Phenylbutazone should not be used for 8-12 days following mifepristone administration. Avoid combination

Pimavanserin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Pimavanserin. Management: Decrease the pimavanserin dose to 10 mg daily when combined with strong CYP3A4 inhibitors. Consider therapy modification

Pimecrolimus: CYP3A4 Inhibitors (Strong) may decrease the metabolism of Pimecrolimus. Monitor therapy

Pimozide: MiFEPRIStone may enhance the QTc-prolonging effect of Pimozide. MiFEPRIStone may increase the serum concentration of Pimozide. Management: Avoid pimozide during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Piperaquine: CYP3A4 Inhibitors (Strong) may enhance the QTc-prolonging effect of Piperaquine. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Piperaquine. Management: Avoid concomitant use of piperaquine and strong CYP3A4 inhibitors when possible. If the combination cannot be avoided, frequent ECG monitoring is recommended due to the risk for QTc prolongation. Exceptions are discussed separately. Consider therapy modification

Polatuzumab Vedotin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Polatuzumab Vedotin. Exposure to unconjugated MMAE, the cytotoxic small molecule component of polatuzumab vedotin, may be increased. Monitor therapy

PONATinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of PONATinib. Management: Per ponatinib U.S. prescribing information, the adult starting dose of ponatinib should be reduced to 30 mg daily during treatment with any strong CYP3A4 inhibitor. Consider therapy modification

Pranlukast: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Pranlukast. Monitor therapy

Progestins (Contraceptive): MiFEPRIStone may diminish the therapeutic effect of Progestins (Contraceptive). MiFEPRIStone may increase the serum concentration of Progestins (Contraceptive). Management: Women of childbearing potential should use an effective, nonhormonal means of contraception during and 4 weeks following mifepristone treatment. Consider therapy modification

Propafenone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Propafenone. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Monitor therapy

Prothionamide: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

QT-prolonging Agents (Highest Risk): QT-prolonging Agents (Indeterminate Risk - Caution) may enhance the QTc-prolonging effect of QT-prolonging Agents (Highest Risk). Management: Monitor for QTc interval prolongation and ventricular arrhythmias when these agents are combined. Patients with additional risk factors for QTc prolongation may be at even higher risk. Monitor therapy

QUEtiapine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of QUEtiapine. Management: In quetiapine treated patients, reduce quetiapine to one-sixth of regular dose after starting strong CYP3A4 inhibitor. In those on strong CYP3A4 inhibitors, start quetiapine at lowest dose and up-titrate as needed. Exceptions discussed separately. Consider therapy modification

QuiNIDine: MiFEPRIStone may enhance the QTc-prolonging effect of QuiNIDine. MiFEPRIStone may increase the serum concentration of QuiNIDine. Management: Avoid quinidine during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Quinolones: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Quinolones may diminish the therapeutic effect of Blood Glucose Lowering Agents. Specifically, if an agent is being used to treat diabetes, loss of blood sugar control may occur with quinolone use. Monitor therapy

Radotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Radotinib. Avoid combination

Ramelteon: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ramelteon. Monitor therapy

Ranolazine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ranolazine. Avoid combination

Reboxetine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Reboxetine. Consider therapy modification

Red Yeast Rice: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Red Yeast Rice. Specifically, concentrations of lovastatin and related compounds found in Red Yeast Rice may be increased. Avoid combination

Regorafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Regorafenib. Avoid combination

Repaglinide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Repaglinide. Management: The addition of a CYP2C8 inhibitor to this drug combination may substantially increase the magnitude of increase in repaglinide exposure. Monitor therapy

Retapamulin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Retapamulin. Management: Avoid this combination in patients less than 2 years old. No action is required in other populations. Monitor therapy

Ribociclib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ribociclib. Management: Avoid use of ribociclib with strong CYP3A4 inhibitors when possible; if combined use cannot be avoided, reduce ribociclib dose to 400 mg once daily. Exceptions are discussed in separate monographs. Consider therapy modification

Rilpivirine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Rilpivirine. Monitor therapy

RomiDEPsin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of RomiDEPsin. Monitor therapy

Rupatadine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Rupatadine. Avoid combination

Ruxolitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ruxolitinib. Management: This combination should be avoided under some circumstances. See monograph for details. Consider therapy modification

Salicylates: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Salmeterol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Salmeterol. Avoid combination

Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

SAXagliptin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SAXagliptin. Management: Limit the saxagliptin dose to 2.5 mg daily when combined with strong CYP3A4 inhibitors. When using the saxagliptin combination products saxagliptin/dapagliflozin or saxagliptin/dapagliflozin/metformin, avoid use with strong CYP3A4 inhibitors. Consider therapy modification

Selective Serotonin Reuptake Inhibitors: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Sibutramine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Sibutramine. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Sibutramine. Monitor therapy

Sildenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Sildenafil. Management: Use of sildenafil for pulmonary hypertension should be avoided with strong CYP3A4 inhibitors. When used for erectile dysfunction, starting adult dose should be reduced to 25 mg. Maximum adult dose with ritonavir or cobicistat is 25 mg per 48 hours. Consider therapy modification

Silodosin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Silodosin. Avoid combination

Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Simeprevir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Simeprevir. Avoid combination

Simvastatin: MiFEPRIStone may increase the serum concentration of Simvastatin. Management: Avoid simvastatin during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Siponimod: MiFEPRIStone may increase the serum concentration of Siponimod. Management: Coadministration of siponimod with miferpristone, a moderate inhibitor of CYP2C9 and a strong inhibitor of CYP3A4 is not recommended. Avoid combination

Sirolimus: MiFEPRIStone may increase the serum concentration of Sirolimus. Management: Avoid sirolimus during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Solifenacin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Solifenacin. Management: Limit solifenacin doses to 5 mg daily when combined with strong CYP3A4 inhibitors. Consider therapy modification

Sonidegib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Sonidegib. Avoid combination

SORAfenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SORAfenib. Monitor therapy

St John's Wort: May decrease the serum concentration of MiFEPRIStone. Avoid combination

Stiripentol: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Use of stiripentol with CYP3A4 substrates that are considered to have a narrow therapeutic index should be avoided due to the increased risk for adverse effects and toxicity. Any CYP3A4 substrate used with stiripentol requires closer monitoring. Consider therapy modification

SUFentanil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SUFentanil. Management: If a strong CYP3A4 inhibitor is initiated in a patient on sufentanil, consider a sufentanil dose reduction and monitor for increased sufentanil effects and toxicities (eg, respiratory depression). Consider therapy modification

SUNItinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SUNItinib. Management: Avoid when possible. If such a combination cannot be avoided, sunitinib dose decreases are recommended, and vary by indication. See full monograph for details. Consider therapy modification

Suvorexant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Suvorexant. Avoid combination

Tacrolimus (Systemic): MiFEPRIStone may enhance the QTc-prolonging effect of Tacrolimus (Systemic). MiFEPRIStone may increase the serum concentration of Tacrolimus (Systemic). Management: Avoid tacrolimus during and 2 weeks following mifepristone for treatment of hyperglycemia in Cushing's syndrome. The interaction magnitude could be lower with single doses used to terminate pregnancy, but neither effect has been studied clinically. Avoid combination

Tadalafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tadalafil. Management: Recommendations regarding use of tadalafil in patients also receiving strong CYP3A4 inhibitors may vary based on indication and/or international labeling. Consult appropriate product labeling. Consider therapy modification

Tamsulosin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tamsulosin. Avoid combination

Tasimelteon: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tasimelteon. Monitor therapy

Tazemetostat: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tazemetostat. Avoid combination

Temsirolimus: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Temsirolimus. Management: Avoid concomitant use of temsirolimus and strong CYP3A4 inhibitors whenever possible. If combined, decrease temsirolimus dose to 12.5 mg per week and monitor patients for increased temsirolimus effects and toxicities. Consider therapy modification

Tenoxicam: May diminish the therapeutic effect of MiFEPRIStone. Monitor therapy

Terfenadine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Terfenadine. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination

Tetrahydrocannabinol: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Tetrahydrocannabinol. Monitor therapy

Tetrahydrocannabinol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tetrahydrocannabinol. Monitor therapy

Tetrahydrocannabinol and Cannabidiol: CYP2C9 Inhibitors (Moderate) may increase the serum concentration of Tetrahydrocannabinol and Cannabidiol. Specifically, concentrations of tetrahydrocannabinol may be increased. Monitor therapy

Tetrahydrocannabinol and Cannabidiol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tetrahydrocannabinol and Cannabidiol. Monitor therapy

Tezacaftor and Ivacaftor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tezacaftor and Ivacaftor. Management: When combined with strong CYP3A4 inhibitors, tezacaftor/ivacaftor should be administered in the morning, twice a week, approximately 3 to 4 days apart. No evening doses of ivacaftor alone should be administered. Consider therapy modification

Thiotepa: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Thiotepa. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Thiotepa. Management: Thiotepa prescribing information recommends avoiding concomitant use of thiotepa and strong CYP3A4 inhibitors. If concomitant use is unavoidable, monitor for adverse effects and decreased efficacy. Consider therapy modification

Ticagrelor: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Ticagrelor. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ticagrelor. Avoid combination

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Tofacitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tofacitinib. Management: Tofacitinib dose reductions are recommended when combined with strong CYP3A4 inhibitors. Recommended dose adjustments vary by tofacitinib formulation and therapeutic indication. See full monograph for details. Consider therapy modification

Tolterodine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tolterodine. Management: The maximum recommended adult dose of tolterodine is 2 mg/day when used together with a strong CYP3A4 inhibitor. Consider therapy modification

Tolvaptan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tolvaptan. Avoid combination

Toremifene: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Toremifene. Management: Use of toremifene with strong CYP3A4 inhibitors should be avoided if possible. If coadministration is necessary, monitor for increased toremifene toxicities, including QTc interval prolongation. Exceptions are discussed in separate monograph. Consider therapy modification

Trabectedin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Trabectedin. Avoid combination

TraMADol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of TraMADol. Monitor therapy

TraZODone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of TraZODone. Management: Consider the use of a lower trazodone dose and monitor for increased trazodone effects (eg, sedation, QTc prolongation) if combined with strong CYP3A4 inhibitors. Consider therapy modification

Triazolam: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Triazolam. Avoid combination

Ubrogepant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ubrogepant. Avoid combination

Udenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Udenafil. Avoid combination

Ulipristal: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ulipristal. Management: This is specific for when ulipristal is being used for signs/symptoms of uterine fibroids (Canadian indication). When ulipristal is used as an emergency contraceptive, patients receiving this combo should be monitored for ulipristal toxicity. Avoid combination

Upadacitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Upadacitinib. Monitor therapy

Valbenazine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Valbenazine. Management: Reduce the valbenazine dose to 40 mg daily when combined with strong CYP3A4 inhibitors. Consider therapy modification

Vardenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vardenafil. Management: Recommendations regarding concomitant use of vardenafil with strong CYP3A4 inhibitors may vary depending on brand name (e.g., Levitra, Staxyn) or by international labeling. See full drug interaction monograph for details. Consider therapy modification

Vemurafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vemurafenib. Management: Avoid concurrent use of vemurafenib with strong CYP3A4 inhibitors when possible. Consider use of an alternative that is not a strong inhibitor of CYP3A4 as clinically appropriate. Consider therapy modification

Venetoclax: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Venetoclax. Management: This combination is contraindicated during venetoclax initiation and ramp-up in patients with CLL/SLL. Reduced venetoclax doses are required during ramp-up for patients with AML, and reduced doses are required for all patients during maintenance therapy. Consider therapy modification

Vilanterol: May increase the serum concentration of CYP3A4 Inhibitors (Strong). Monitor therapy

Vilazodone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vilazodone. Management: Limit maximum adult vilazodone dose to 20 mg daily in patients receiving strong CYP3A4 inhibitors. The original vilazodone dose can be resumed following discontinuation of the strong CYP3A4 inhibitor. Consider therapy modification

VinCRIStine (Liposomal): CYP3A4 Inhibitors (Strong) may increase the serum concentration of VinCRIStine (Liposomal). Avoid combination

Vindesine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vindesine. Monitor therapy

Vinflunine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vinflunine. Avoid combination

Vorapaxar: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vorapaxar. Avoid combination

Voxelotor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Voxelotor. Management: Avoid concomitant use of voxelotor and strong CYP3A4 inhibitors. If concomitant use is unavoidable, reduce the voxelotor dose to 1,000 mg once daily. Consider therapy modification

Zanubrutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zanubrutinib. Management: Decrease the zanubrutinib dose to 80 mg once daily during coadministration with a strong CYP3A4 inhibitor. Further dose adjustments may be required for zanubrutinib toxicities, refer to prescribing information for details. Consider therapy modification

Zolpidem: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zolpidem. Monitor therapy

Zopiclone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zopiclone. Management: The initial starting adult dose of zopiclone should not exceed 3.75 mg if combined with a strong CYP3A4 inhibitor. Monitor patients for signs and symptoms of zopiclone toxicity if these agents are combined. Consider therapy modification

Zuclopenthixol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zuclopenthixol. Management: Consider zuclopenthixol dosage reduction with concomitant use of a strong CYP3A4 inhibitor (eg, ketoconazole) in poor CYP2D6 metabolizers or with strong CYP2D6 inhibitors (eg, paroxetine). Monitor for increased zuclopenthixol levels/toxicity. Consider therapy modification

Test Interactions

When used for the treatment of hyperglycemia in patients with Cushing syndrome, serum cortisol concentrations remain elevated and may increase, and cannot be used for monitoring.

Adverse Reactions

Adverse reactions occur with treatment of hyperglycemia in patients with Cushing syndrome unless otherwise specified.

>10%:

Cardiovascular: Peripheral edema (26%), hypertension (24%)

Central nervous system: Fatigue (hyperglycemia: 48%; pregnancy termination: 10%), headache (hyperglycemia: 44%; pregnancy termination: 2% to 31%), dizziness (hyperglycemia: 22%; pregnancy termination: 1% to 12%), pain (14%)

Endocrine & metabolic: Hypokalemia (34% to 44%), abnormal thyroid function test (18%)

Gastrointestinal: Abdominal cramps (pregnancy termination: 96%), nausea (pregnancy termination: 43% to 61%; hyperglycemia: 48%), vomiting (hyperglycemia and pregnancy termination: 18% to 26%), decreased appetite (20%), diarrhea (hyperglycemia and pregnancy termination: 12% to 20%), xerostomia (18%)

Genitourinary: Uterine cramps (pregnancy termination: 83%), endometrium disease (hypertrophy: 38%), vaginal hemorrhage (14%; when used for pregnancy termination, vaginal bleeding for 9 to 16 days is expected, with the first 2 days being the heaviest; 8% of these patients experience bleeding for ≥30 days)

Neuromuscular & skeletal: Arthralgia (30%), back pain (hyperglycemia and pregnancy termination: 9% to 16%), myalgia (14%), limb pain (12%)

Respiratory: Dyspnea (16%), sinusitis (hyperglycemia: 14%; pregnancy termination: 2%), nasopharyngitis (12%)

1% to 10%:

Cardiovascular: Edema (5% to 10%), pitting edema (5% to 10%), syncope (pregnancy termination: 1% to 2%)

Central nervous system: Anxiety (hyperglycemia: 10%; pregnancy termination: 2%), drowsiness (10%), flank pain (5% to 10%), malaise (5% to 10%), insomnia (pregnancy termination: 3%), rigors (pregnancy termination: 3%)

Dermatologic: Pruritus (4%), skin rash (4%)

Endocrine & metabolic: Hypoglycemia (5% to 10%), increased serum triglycerides (5% to 10%), increased thirst (5% to 10%), adrenocortical insufficiency (4%)

Gastrointestinal: Anorexia (10%), constipation (10%), abdominal pain (5% to 10%), gastroesophageal reflux disease (5% to 10%), dyspepsia (pregnancy termination: 3%)

Genitourinary: Uterine hemorrhage (pregnancy termination: 5%), vaginitis (pregnancy termination: 3%), leukorrhea (pregnancy termination: 2%), pelvic pain (pregnancy termination: 2%), endometriosis (pregnancy termination: ≤1%), salpingitis (pregnancy termination: ≤1%), pelvic inflammatory disease (pregnancy termination: ≤1%)

Hematologic & oncologic: Decreased hemoglobin (pregnancy termination: 6%; >2 g/dL), anemia (pregnancy termination: 2%)

Infection: Viral infection (pregnancy termination: 4%)

Neuromuscular & skeletal: Musculoskeletal chest pain (5% to 10%), weakness (pregnancy termination: 2%), leg pain (pregnancy termination: 2%)

Miscellaneous: Fever (pregnancy termination: 4%)

Frequency not defined: Endocrine & metabolic: Decreased HDL cholesterol

<1%, postmarketing, and/or case reports: Acute pancreatitis, adult respiratory distress syndrome, bacterial infection (including an ectopic bacteria such as Clostridium sordellii), disseminated intravascular coagulopathy, dyspnea, ectopic pregnancy (rupture), exacerbation of Crohn's disease, hypersensitivity reaction (including urticaria), hypotension, infection (post-abortion), loss of consciousness, myocardial infarction, pelvic infection, prolonged Q-T interval on ECG, sepsis, septic shock, tachycardia, toxic shock syndrome

Warnings/Precautions

Concerns related to adverse effects:

  • Adrenal insufficiency: When used for the treatment of hyperglycemia in patients with Cushing syndrome, adrenal insufficiency may occur. Serum cortisol concentrations remain elevated and may increase and cannot be used for monitoring. If signs and symptoms of adrenal insufficiency occur (eg, fatigue, hypoglycemia, hypotension, nausea, weakness), discontinue mifepristone and administer glucocorticoids (high doses may be needed). Following resolution, treatment may be resumed at a lower dose; evaluate patient for precipitating causes (eg, infection, trauma).
  • Bacterial infections: [US Boxed Warning]: When used for the termination of pregnancy, bacterial infections (eg, Clostridium sordellii) have been reported following use of this product and may have an atypical presentation. In rare cases, these infections may be serious and/or fatal, with septic shock as a potential complication. A causal relationship has not been established. A fever of ≥38°C (100.4°F) for > 4 hours, abdominal pain, or pelvic tenderness should prompt evaluation; however, healthcare professionals are warned that atypical presentations of serious infection without these symptoms have also been noted. Patients presenting with nausea, vomiting, diarrhea, or weakness, with or without abdominal pain or fever, should be evaluated for serious bacterial infection when symptoms occur >24 hours after taking misoprostol. Patients with Cushing syndrome may be at risk for opportunistic infections such as Pneumocystis jirovecii pneumonia.
  • Bleeding: Regardless of indication, endometrial proliferation is promoted by mifepristone, resulting in endometrial thickening, cystic dilation of endometrial glands, and vaginal bleeding. [US Boxed Warning]: When used for the termination of pregnancy, patients should be counseled to seek medical attention in cases of excessive bleeding. Bleeding occurs and should be expected (average 9 to 16 days, may be ≥30 days). In some cases, bleeding may be prolonged and heavy and may be a sign of incomplete abortion or other complications, potentially leading to hypovolemic shock; the manufacturer cites soaking through 2 thick sanitary pads per hour for 2 consecutive hours as an example of excessive bleeding. Bleeding may require blood transfusion (rare), curettage, saline infusions, and/or vasoconstrictors. Patients should be instructed to seek medical attention if prolonged heavy vaginal bleeding occurs. When used for termination of pregnancy, use is contraindicated in women with hemorrhagic disorders or those using anticoagulants; use caution in women with severe anemia, hypocoagulability or hemostatic disorders. When used for the treatment of hyperglycemia in patients with Cushing syndrome, use caution in women with hemorrhagic disorders or women using anticoagulants and evaluate unexplained vaginal bleeding; use is contraindicated with a history of unexplained vaginal bleeding.
  • Hypokalemia: May occur at any time during therapy when used to control hyperglycemia in patients with Cushing syndrome. Correct hypokalemia prior to initiation of treatment; monitor potassium levels closely with therapy.
  • QT prolongation: May prolong the QTc interval (dose related); use caution with other QT-prolonging agents.

Disease-related concerns:

  • Cardiovascular disease: Because mifepristone does not reduce serum cortisol concentrations, mineralocorticoid receptors in cardiac tissue may be activated; use caution in patients with Cushing syndrome who also have heart failure or coronary vascular disease.
  • Diabetes: Safety and efficacy have not been established for use in insulin-dependent diabetes mellitus.
  • Hepatic impairment: In patients with moderate hepatic impairment, a large variability in exposure to mifepristone and its metabolites was observed at doses of 600 mg/day.
  • Renal impairment: In patients with severe renal impairment, exposure to mifepristone and its metabolites was increased and a large variability in exposure was observed following multiple doses used in patients with Cushing syndrome.

Concurrent drug therapy issues:

  • Corticosteroids: Use of mifepristone for the treatment of hyperglycemia in patients with Cushing syndrome may antagonize the effects of steroids used for other conditions. Use is contraindicated when steroids are required for lifesaving indications.
  • Drug-drug interactions: When used for the treatment of hyperglycemia in patients with Cushing syndrome, potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Special populations:

  • Pregnancy: [US Boxed Warning]: Use of mifepristone will result in termination of pregnancy. When used to control hyperglycemia in women with Cushing syndrome, pregnancy must be excluded before the initiation of treatment with mifepristone and prevented during treatment and for 1 month after stopping treatment by the use of a nonhormonal, medically acceptable method of contraception unless the patient has had a surgical sterilization, in which case, no additional contraception is needed. Pregnancy must also be excluded if treatment is interrupted for more than 14 days in females of reproductive potential.

Other warnings/precautions:

  • Confirmation of terminated pregnancy: When used for the termination of pregnancy, confirmation of pregnancy termination by clinical exam, human Chorionic Gonadotropin (hCG), and/or ultrasound must be made 7 to 14 days following treatment. Manufacturer recommends surgical evacuation to manage ongoing pregnancy after medical abortion. Prescriber should determine in advance whether they will provide such care themselves or through other providers. Preventive measures to prevent rhesus immunization must be taken prior to surgical abortion.
  • Ectopic pregnancy: Mifepristone is not effective in terminating ectopic pregnancies and is contraindicated in patients with confirmed or suspected ectopic pregnancy. Healthcare providers should be alert for signs/symptoms which may be related to undiagnosed ectopic pregnancy in any patient undergoing a medical abortion; ectopic pregnancy may have been missed even if the patient underwent ultrasonography prior to mifepristone administration.
  • Intrauterine device: When used for the termination of pregnancy, remove any intrauterine device before treatment begins. Consider the possibility of ectopic pregnancy in women who become pregnant with an IUD in place.
  • Experienced physician: When used for the termination of pregnancy, to be administered only by physicians who can date pregnancy, diagnose ectopic pregnancies, provide access to surgical abortion (if needed), and can provide access to emergency care. Medication will be distributed directly to these physicians following signed agreement with the distributor. Must be administered under supervision by the qualified physician.
  • Medication guide: [US Boxed Warning]: When used for the termination of pregnancy, patients undergoing treatment with mifepristone should be instructed to bring their medication guide with them when obtaining treatment from an emergency room or healthcare provider that did not prescribe the medication initially in order to identify that they are undergoing a medical abortion.
  • Patient education: [US Boxed Warning]: When used for the termination of pregnancy, patient must be instructed of the treatment procedure and expected effects. A signed agreement form must be kept in the patient's file. Prescriber should also give the patient clear instructions on whom to call and what to do in the event of an emergency following administration of therapy. Consider appropriate location of initiating therapy; expulsion of pregnancy is expected within 2 to 24 hours after taking misoprostol
  • Pregnancy dating: Pregnancy is dated from day 1 of last menstrual period (presuming a 28-day cycle, ovulation occurring midcycle). Pregnancy duration can be determined using menstrual history and clinical examination. Ultrasound should be used if duration of pregnancy is uncertain or if ectopic pregnancy is suspected.
  • REMS program: [US Boxed Warning]: When used for the termination of pregnancy, because of the risks of serious infection and bleeding, mifepristone is only available through the Mifeprex REMS Program. Prescribers must be certified with the program by completing the prescriber agreement form and patients must sign a patient agreement form. Mifepristone is only dispensed to patients in clinics, medical offices, and hospitals by or under the supervision of a certified prescriber. Mifepristone is only available through Danco Laboratories’ distributor; for more information, call 1-877-432-7596.

Monitoring Parameters

Treatment of hyperglycemia in patients with Cushing syndrome: Signs and symptoms of adrenal insufficiency (serum cortisol concentrations will not be accurate); thyroid function; serum potassium (1 to 2 weeks after initiating dose or dose increase, then periodically thereafter); serum glucose and psychiatric symptoms (may show response to therapy within 6 weeks); cushingoid appearance (acne, hirsutism, striae, weight may take >2 months of therapy to show improvement); vaginal ultrasound in women (annually)

Pregnancy-related uses: Prior to termination of pregnancy, confirm pregnancy and Rh status; assess hemoglobin and hematocrit if anemia is suspected (ACOG 143 2014). Following procedure: Clinical exam, human Chorionic Gonadotropin (hCG) testing, and/or ultrasound to confirm complete termination of pregnancy; hemoglobin, hematocrit, and red blood cell count in cases of heavy bleeding. Consider CBC in any patient who reports nausea, vomiting, or diarrhea and weakness with or without abdominal pain, and without fever or other signs of infection more than 24 hours after administration of misoprostol. When used for medical management of early pregnancy loss, evaluate Rh status; evaluate response to treatment within 7 days after the first dose (ACOG 200 2018).

Pregnancy

Pregnancy Considerations

Mifepristone is contraindicated for use in pregnant women when used to control hyperglycemia in Cushing syndrome.

Korlym: [US Boxed Warning]: Mifepristone is a potent antagonist of progesterone and cortisol via the progesterone and glucocorticoid (GR-II) receptors, respectively. The antiprogestational effects will result in the termination of pregnancy. When used to control hyperglycemia in women with Cushing syndrome, pregnancy must be excluded before the initiation of treatment with mifepristone and prevented during treatment and for 1 month after stopping treatment by the use of a nonhormonal, medically acceptable method of contraception unless the patient has had a surgical sterilization, in which case, no additional contraception is needed. Pregnancy must also be excluded if treatment is interrupted for more than 14 days in females of reproductive potential.

Mifeprex: This medication is used to terminate pregnancy; there are no approved treatment indications for its use during pregnancy. If treatment fails, there is a risk of fetal malformation. In sexually active women, pregnancy can occur prior to the first menstrual period following treatment. Appropriate contraception can be started as soon as termination of pregnancy is confirmed or before sexual intercourse is resumed.

Patient Education

What is this drug used for?

  • It is used to end a pregnancy.
  • It is used to lower blood sugar in patients with Cushing syndrome.

Frequently reported side effects of this drug

  • Fatigue
  • Back pain
  • Abdominal cramps
  • Vaginal discharge
  • Constipation
  • Lack of appetite
  • Dry mouth
  • Heartburn
  • Joint pain
  • Sore throat
  • Stuffy nose

Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:

  • Infection
  • Persistent fever
  • Severe abdominal pain
  • Fast heartbeat
  • Passing out
  • Severe vaginal bleeding like soaking two pads per hour
  • Severe nausea
  • Vomiting
  • Severe diarrhea
  • Severe loss of strength and energy
  • Severe dizziness
  • Severe headache
  • Shortness of breath
  • Severe vaginal pain, itching, and discharge
  • Pelvic pain
  • Adrenal gland problems like severe nausea, vomiting, severe dizziness, passing out, muscle weakness, severe fatigue, mood changes, lack of appetite, or weight loss
  • Low potassium like muscle pain or weakness, muscle cramps, or an abnormal heartbeat
  • Abnormal heartbeat
  • Vision changes
  • Anxiety
  • Chest pain
  • Swelling of arms or legs
  • Trouble sleeping
  • Low blood sugar like dizziness, headache, fatigue, feeling weak, shaking, fast heartbeat, confusion, increased hunger, or sweating
  • Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Source: Wolters Kluwer Health. Last updated January 30, 2020.