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Estradiol and Norgestimate

Generic name: estradiol/norgestimate systemic

Brand names: Ortho-Prefest, Prefest

Boxed Warning

Cardiovascular disease:

Estrogens and progestins should not be used for the prevention of cardiovascular disease. The Women's Health Initiative (WHI) study reported increased risks of myocardial infarction, stroke, pulmonary emboli, and deep vein thrombosis in postmenopausal women 50 to 79 years of age during 5 years of treatment with oral conjugated equine estrogens (CE 0.625 mg) combined with medroxyprogesterone acetate (MPA 2.5 mg) relative to placebo.

Breast cancer:

The Women's Health Initiative (WHI) study reported an increased risk of invasive breast cancer.

Dementia:

The Women's Health Initiative Memory Study (WHIMS), a substudy of WHI, reported increased risk of developing probable dementia in postmenopausal women 65 years of age or older during 4 years of treatment with oral conjugated estrogens plus medroxyprogesterone acetate relative to placebo. It is unknown whether this finding applies to younger postmenopausal women.

Risk vs benefit:

Other doses of oral conjugated estrogens with medroxyprogesterone acetate, and other combinations and dosage forms of estrogens and progestins were not studied in the WHI clinical trials and, in the absence of comparable data, these risks should be assumed to be similar. Because of these risks, estrogens with or without progestins should be prescribed at the lowest effective doses and for the shortest duration consistent with treatment goals and risks for the individual woman.

Dosage Forms

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

Tablet, oral:

Prefest: Estradiol 1 mg [15 peach tablets] and estradiol 1 mg and norgestimate 0.09 mg [15 white tablets]

Pharmacology

Mechanism of Action

Estrogens are responsible for the development and maintenance of the female reproductive system and secondary sexual characteristics. Estradiol is the principle intracellular human estrogen and is more potent than estrone and estriol at the receptor level; it is the primary estrogen secreted prior to menopause. Following menopause, estrone and estrone sulfate are more highly produced. Estrogens modulate the pituitary secretion of gonadotropins, luteinizing hormone, and follicle-stimulating hormone through a negative feedback system; estrogen replacement reduces elevated levels of these hormones in postmenopausal women.

Progestins inhibit gonadotropin production which then prevents follicular maturation and ovulation. In women with adequate estrogen, progestins transform a proliferative endometrium into a secretory endometrium; when administered with estradiol, reduces the incidence of endometrial hyperplasia and risk of adenocarcinoma.

Pharmacokinetics/Pharmacodynamics

Metabolism

Norgestimate: Forms 17-deacetylnorgestimate (major active metabolite) and other metabolites; first-pass effect

Excretion

Norgestimate: Norgestimate metabolites: Urine and feces

Time to Peak

Norgestimate: ~2 hours

Half-Life Elimination

Norgestimate: 17-deacetylnorgestimate: 37 hours

Protein Binding

Norgestimate: 17-deacetylnorgestimate: 99%

Use: Labeled Indications

Osteoporosis prevention: Prevention of osteoporosis

Limitations of use: For use only in women at significant risk of postmenopausal osteoporosis; consider use of nonestrogen medications.

Vasomotor symptoms associated with menopause: Treatment of moderate to severe vasomotor symptoms

Vulvar and vaginal atrophy associated with menopause: Treatment of moderate to severe symptoms of vulvar and vaginal atrophy

Limitations of use: When used solely for the treatment of vulvar and vaginal atrophy, topical vaginal products should be considered.

Note: The International Society for the Study of Women’s Sexual Health and The North American Menopause Society have endorsed the term genitourinary syndrome of menopause (GSM) as new terminology for vulvovaginal atrophy. The term GSM encompasses all genital and urinary signs and symptoms associated with a loss of estrogen due to menopause Portman 2014.

Contraindications

Hypersensitivity to estradiol, norgestimate, or any component of the formulation; undiagnosed abnormal genital bleeding; DVT or PE (current or history of); active or history of arterial thromboembolic disease (eg, stroke, MI); breast cancer (known, suspected or history of); estrogen-dependent tumor (known or suspected); hepatic impairment or disease; pregnancy.

Canadian labeling: Additional contraindications (not in US labeling): Estrogen/progestin-dependent neoplasia (known, suspected, or history of); endometrial hyperplasia; active thrombophlebitis; partial or complete loss of vision due to ophthalmic vascular disease; classical migraine.

Dosage and Administration

Dosing: Adult

General dosing guidelines: When treating symptoms of menopause, hormone therapy should be evaluated routinely for appropriate dose, duration, and route of administration for each individual patient based on treatment goals, risk factors, and overall health (NAMS 2017). Combined estrogen/progestin therapy is indicated for postmenopausal persons with a uterus to decrease the risk of endometrial cancer. Individuals who have had a hysterectomy generally do not need a progestin; however, one may be needed if there is a history of endometriosis. Adjust dose based on patient response.

Osteoporosis prevention; Vasomotor symptoms associated with menopause; Vulvar and vaginal atrophy associated with menopause: Oral: Treatment is cyclical and consists of the following: One tablet of estradiol 1 mg (pink tablet) once daily for 3 days, followed by 1 tablet of estradiol 1 mg and norgestimate 0.09 mg (white tablet) once daily for 3 days; repeat sequence continuously. Note: This dose may not be the lowest effective combination for these indications. In case of a missed tablet, restart therapy with next available tablet in sequence (taking only 1 tablet each day).

Dosing: Geriatric

Note: Women >65 years of age should be assessed for benefits and risks of treatment; possible adjustments to safer lower-dose and/or route of administration should be considered (ACOG 565 2013; NAMS 2017). The Beers Criteria recommends avoiding systemic estrogen therapy in patients ≥65 years of age (independent of diagnosis or condition) (Beers Criteria [AGS 2019]).

Refer to adult dosing.

Administration

In case of a missed tablet for one or more days, restart therapy with next available tablet in sequence (taking only 1 tablet each day).

Dietary Considerations

Ensure adequate calcium and vitamin D intake when used for the prevention of osteoporosis.

Storage

Store at 25°C (77°F).

Drug Interactions

Acitretin: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Management: Given the potential for progestin-only preparations to fail to prevent pregnancy during acitretin therapy, such products should not be relied upon. Alternative, nonhormonal forms of contraception must be employed during acitretin therapy. Consider therapy modification

Ajmaline: Estrogen Derivatives may enhance the adverse/toxic effect of Ajmaline. Specifically, the risk for cholestasis may be increased. Monitor therapy

Anastrozole: Estrogen Derivatives may diminish the therapeutic effect of Anastrozole. Avoid combination

Anthrax Immune Globulin (Human): Estrogen Derivatives may enhance the thrombogenic effect of Anthrax Immune Globulin (Human). Monitor therapy

Anticoagulants: Estrogen Derivatives may diminish the anticoagulant effect of Anticoagulants. More specifically, the potential prothrombotic effects of some estrogens and progestin-estrogen combinations may counteract anticoagulant effects. Management: Carefully weigh the prospective benefits of estrogens against the potential increased risk of procoagulant effects and thromboembolism. Use is considered contraindicated under some circumstances. Refer to related guidelines for specific recommendations. Consider therapy modification

Anticoagulants: Progestins may diminish the therapeutic effect of Anticoagulants. More specifically, the potential prothrombotic effects of some progestins and progestin-estrogen combinations may counteract anticoagulant effects. Management: Carefully weigh the prospective benefits of progestins against the potential increased risk of procoagulant effects and thromboembolism. Use is considered contraindicated under some circumstances. Refer to related guidelines for specific recommendations. Consider therapy modification

Antidiabetic Agents: Hyperglycemia-Associated Agents may diminish the therapeutic effect of Antidiabetic Agents. Monitor therapy

Aprepitant: May decrease the serum concentration of Progestins (Contraceptive). Management: Alternative or additional methods of contraception should be used both during treatment with aprepitant or fosaprepitant and for at least one month following the last aprepitant/fosaprepitant dose. Consider therapy modification

Artemether: May decrease the serum concentration of Progestins (Contraceptive). Management: Consider the use of an alternative (i.e., non-hormonal) means of contraception in all women of childbearing potential who are using artemether. Consider therapy modification

Ascorbic Acid: May increase the serum concentration of Estrogen Derivatives. Monitor therapy

Asunaprevir: May decrease serum concentrations of the active metabolite(s) of Norgestimate. Management: For patients using hormone-based contraception, a high-dose oral contraceptive containing at least 30 mcg of ethinyl estradiol combined with norethindrone acetate/norethindrone is recommended during treatment with asunaprevir. Consider therapy modification

Atazanavir: May increase the serum concentration of Progestins (Contraceptive). However, atazanavir may lead to decreased ethinyl estradiol concentrations and decreased effectiveness of oral contraceptive products. Management: Consider an alternative or additional method of contraception, particularly with combined estrogen/progestin products. Depot medroxyprogesterone acetate may be used without a need for additional contraception. Consider therapy modification

Barbiturates: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Management: Use of alternative, nonhormonal contraceptives is recommended. Consider therapy modification

Bexarotene (Systemic): May decrease the serum concentration of Progestins (Contraceptive). Management: Women of childbearing potential receiving bexarotene should use two reliable forms of contraception (including at least one nonhormonal form). Consider therapy modification

Bile Acid Sequestrants: May decrease the serum concentration of Progestins (Contraceptive). Management: Administer oral progestin-containing contraceptives at least 1 to 4 hours prior to or 4 to 6 hours after administration of a bile acid sequestrant. Consider therapy modification

Bosentan: May decrease the serum concentration of Progestins (Contraceptive). Management: Use an alternative (i.e., non-hormonal) means of contraception for all women of childbearing potential who are using bosentan, and do not rely on hormonal contraceptives alone. Consider therapy modification

Brigatinib: May decrease the serum concentration of Progestins (Contraceptive). Management: Females of childbearing potential should use an alternative, non-hormonal contraceptive during brigatinib therapy and for at least 4 months after the final brigatinib dose. Consider therapy modification

C1 inhibitors: Estrogen Derivatives may enhance the thrombogenic effect of C1 inhibitors. Monitor therapy

C1 inhibitors: Progestins may enhance the thrombogenic effect of C1 inhibitors. Monitor therapy

CarBAMazepine: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Management: Use of alternative, nonhormonal contraceptives is recommended. Consider therapy modification

Carfilzomib: May enhance the thrombogenic effect of Progestins (Contraceptive). Management: Consider alternative, non-hormonal methods of contraception in patients requiring therapy with carfilzomib. Consider therapy modification

Cenobamate: May decrease the serum concentration of Hormonal Contraceptives. Management: Women should use additional or alternative non-hormonal birth control while taking cenobamate. Consider therapy modification

Chenodiol: Estrogen Derivatives may diminish the therapeutic effect of Chenodiol. Management: Monitor clinical response to chenodiol closely when used together with any estrogen derivative. Monitor therapy

Cladribine: May diminish the therapeutic effect of Hormonal Contraceptives. Management: Women using systemically acting hormonal contraceptives should add a barrier method during cladribine dosing and for at least 4 weeks after the last dose in each treatment course. Consider therapy modification

CloBAZam: May decrease the serum concentration of Progestins (Contraceptive). Consider therapy modification

CloZAPine: CYP1A2 Inhibitors (Weak) 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

Cobicistat: May increase the serum concentration of Progestins (Contraceptive). Management: Consider an alternative, nonhormone-based contraceptive in patients receiving cobicistat-containing products. Drospirenone is specifically contraindicated with atazanavir and cobicistat. Consider therapy modification

Corticosteroids (Systemic): Estrogen Derivatives may increase the serum concentration of Corticosteroids (Systemic). Monitor therapy

Cosyntropin: Estrogen Derivatives may diminish the diagnostic effect of Cosyntropin. Management: Discontinue estrogen containing drugs 4 to 6 weeks prior to cosyntropin (ACTH) testing. Consider therapy modification

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

CYP3A4 Inducers (Strong): May increase the metabolism of CYP3A4 Substrates (High risk with Inducers). Management: Consider an alternative for one of the interacting drugs. Some combinations may be specifically contraindicated. Consult appropriate manufacturer labeling. Consider therapy modification

CYP3A4 Inhibitors (Moderate): May increase the serum concentration of Estrogen Derivatives. Monitor therapy

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

Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Seek alternatives to the CYP3A4 substrate when possible. If concomitant therapy cannot be avoided, monitor clinical effects of the substrate closely (particularly therapeutic effects). Consider therapy modification

Dabrafenib: May decrease the serum concentration of Progestins (Contraceptive). Management: Females of reproductive potential should use an alternative, highly effective, non-hormonal means of contraception during and at least 2 weeks (dabrafenib alone) or 4 months (dabrafenib + trametinib) after discontinuation of dabrafenib treatment. Consider therapy modification

Dantrolene: Estrogen Derivatives may enhance the hepatotoxic effect of Dantrolene. Monitor therapy

Darunavir: May decrease the serum concentration of Progestins (Contraceptive). Management: Consider using an alternative or additional means of contraception. Injected depot medroxyprogesterone acetate may be used without a need for additional contraception. Consider therapy modification

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

Dehydroepiandrosterone: May enhance the adverse/toxic effect of Estrogen Derivatives. Avoid combination

Efavirenz: May decrease serum concentrations of the active metabolite(s) of Norgestimate. Management: Use a reliable barrier contraceptive if efavirenz is used in combination with norgestimate. Continue using barrier contraception for 12 weeks after discontinuation of efavirenz. Consider therapy modification

Elexacaftor, Tezacaftor, and Ivacaftor: Hormonal Contraceptives may enhance the adverse/toxic effect of Elexacaftor, Tezacaftor, and Ivacaftor. Specifically, the risk for rash may be increased. Monitor therapy

Encorafenib: May decrease the serum concentration of Progestins (Contraceptive). Avoid combination

Enzalutamide: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Concurrent use of enzalutamide with CYP3A4 substrates that have a narrow therapeutic index should be avoided. Use of enzalutamide and any other CYP3A4 substrate should be performed with caution and close monitoring. Consider therapy modification

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

Erdafitinib: May increase the serum concentration of P-glycoprotein/ABCB1 Substrates. Monitor therapy

Eslicarbazepine: May decrease the serum concentration of Progestins (Contraceptive). Management: Alternative, non-hormonal means of birth control should be considered for women of child-bearing potential. Consider therapy modification

Exemestane: Estrogen Derivatives may diminish the therapeutic effect of Exemestane. Avoid combination

Exenatide: May decrease the serum concentration of Progestins (Oral Contraceptive). Management: Administer oral contraceptives at least one hour prior to exenatide. Consider therapy modification

Felbamate: May decrease the serum concentration of Progestins (Contraceptive). Management: Contraceptive failure is possible. Use of an alternative, nonhormonal method of contraception is recommended. Consider therapy modification

Flibanserin: Progestins (Contraceptive) may increase the serum concentration of Flibanserin. Monitor therapy

Fosamprenavir: Progestins (Contraceptive) may decrease serum concentrations of the active metabolite(s) of Fosamprenavir. Fosamprenavir may decrease the serum concentration of Progestins (Contraceptive). Management: Consider using an alternative or additional means of contraception. Injected depot medroxyprogesterone acetate may be used without a need for additional contraception. Consider therapy modification

Fosaprepitant: May decrease the serum concentration of Progestins (Contraceptive). The active metabolite aprepitant is likely responsible for this effect. Management: Alternative or additional methods of contraception should be used both during treatment with aprepitant or fosaprepitant and for at least one month following the last aprepitant/fosaprepitant dose. Consider therapy modification

Fosphenytoin: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Management: Contraceptive failure is possible. Use of an alternative, nonhormonal contraceptive is recommended. Consider therapy modification

Griseofulvin: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Avoid combination

Hemin: Estrogen Derivatives may diminish the therapeutic effect of Hemin. Avoid combination

Herbs (Estrogenic Properties): May enhance the adverse/toxic effect of Estrogen Derivatives. Monitor therapy

Herbs (Progestogenic Properties) (eg, Bloodroot, Yucca): May enhance the adverse/toxic effect of Progestins. Monitor therapy

Hyaluronidase: Estrogen Derivatives may diminish the therapeutic effect of Hyaluronidase. Management: Patients receiving estrogens (particularly at larger doses) may not experience the desired clinical response to standard doses of hyaluronidase. Larger doses of hyaluronidase may be required. Consider therapy modification

Immune Globulin: Estrogen Derivatives may enhance the thrombogenic effect of Immune Globulin. Monitor therapy

Indium 111 Capromab Pendetide: Estrogen Derivatives may diminish the diagnostic effect of Indium 111 Capromab Pendetide. Avoid combination

Ivosidenib: May decrease the serum concentration of Progestins (Contraceptive). Management: Consider alternative methods of contraception (ie, non-hormonal) in patients receiving ivosidenib. Consider therapy modification

Ixazomib: May decrease the serum concentration of Progestins (Contraceptive). More specifically, use of ixazomib with dexamethasone may decrease the serum concentrations of contraceptive progestins. Management: Patients of childbearing potential should use a nonhormonal barrier contraceptive during and 90 days following ixazomib treatment. Avoid combination

LamoTRIgine: May decrease the serum concentration of Progestins (Contraceptive). Monitor therapy

LamoTRIgine: Estrogen Derivatives may decrease the serum concentration of LamoTRIgine. Monitor therapy

Lasmiditan: May increase the serum concentration of P-glycoprotein/ABCB1 Substrates. Avoid combination

Lenalidomide: Estrogen Derivatives may enhance the thrombogenic effect of Lenalidomide. Monitor therapy

Lesinurad: May decrease the serum concentration of Progestins (Contraceptive). Management: Use of an additional, nonhormonal contraceptive is recommended in patients being treated with lesinurad who desire effective contraception. Consider therapy modification

Lixisenatide: May decrease the serum concentration of Progestins (Contraceptive). Management: Administer oral contraceptives 1 hour before or at least 11 hours after administration of lixisenatide. Consider therapy modification

Lopinavir: May decrease the serum concentration of Progestins (Contraceptive). Lopinavir may increase the serum concentration of Progestins (Contraceptive). Management: Consider using an alternative or additional means of contraception. Injected depot medroxyprogesterone acetate and etonogestrel implants may be used without a need for additional contraception. 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

Lumacaftor and Ivacaftor: May decrease the serum concentration of Hormonal Contraceptives. Management: Do not rely on hormone-based contraceptives with concurrent use of lumacaftor/ivacaftor; an alternative, non-hormonal, method of contraception should be used if this combination is required. Consider therapy modification

Metreleptin: May decrease the serum concentration of Progestins (Contraceptive). Metreleptin may increase the serum concentration of Progestins (Contraceptive). Monitor therapy

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

Mitotane: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Doses of CYP3A4 substrates may need to be adjusted substantially when used in patients being treated with mitotane. Consider therapy modification

Mivacurium: Estrogen Derivatives may increase the serum concentration of Mivacurium. Monitor therapy

Mycophenolate: May decrease the serum concentration of Progestins (Contraceptive). Management: Use of an additional or alternative (nonhormonal) method of contraception should be considered. Consider therapy modification

Nelfinavir: May decrease the serum concentration of Progestins (Contraceptive). Management: Use an alternative or additional method of contraception due to possibly decreased contraceptive effectiveness. Injected depot medroxyprogesterone acetate does not appear to participate in this interaction. Consider therapy modification

Nonsteroidal Anti-Inflammatory Agents (COX-2 Selective): May enhance the thrombogenic effect of Estrogen Derivatives. Nonsteroidal Anti-Inflammatory Agents (COX-2 Selective) may increase the serum concentration of Estrogen Derivatives. Monitor therapy

Ospemifene: Estrogen Derivatives may enhance the adverse/toxic effect of Ospemifene. Estrogen Derivatives may diminish the therapeutic effect of Ospemifene. Avoid combination

OXcarbazepine: May decrease the serum concentration of Progestins (Contraceptive). Management: Contraceptive failure is possible. Use of an additional or alternative, nonhormonal method of contraception is recommended. Consider therapy modification

Perampanel: May decrease the serum concentration of Progestins (Contraceptive). Management: Patients should use an alternative, nonhormonal-based form of contraception both during the concurrent use of perampanel and for 1 month after discontinuing perampanel. Consider therapy modification

P-glycoprotein/ABCB1 Inhibitors: May increase the serum concentration of P-glycoprotein/ABCB1 Substrates. P-glycoprotein inhibitors may also enhance the distribution of p-glycoprotein substrates to specific cells/tissues/organs where p-glycoprotein is present in large amounts (e.g., brain, T-lymphocytes, testes, etc.). Monitor therapy

Phenytoin: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Management: Contraceptive failure is possible. Use of an alternative, nonhormonal contraceptive is recommended. Consider therapy modification

Pitolisant: May decrease the serum concentration of Hormonal Contraceptives. Management: Patients using hormonal contraception should be advised to use an alternative non-hormonal contraceptive method during treatment with pitolisant and for at least 21 days after discontinuation of pitolisant treatment. Consider therapy modification

Pomalidomide: May enhance the thrombogenic effect of Estrogen Derivatives. Management: Canadian pomalidomide labeling recommends caution with use of hormone replacement therapy and states that hormonal contraceptives are not recommended. US pomalidomide labeling does not contain these specific recommendations. Consider therapy modification

Pomalidomide: Progestins may enhance the thrombogenic effect of Pomalidomide. Management: Canadian pomalidomide labeling recommends caution with use of hormone replacement therapy and states that hormonal contraceptives are not recommended. US pomalidomide labeling does not contain these specific recommendations. Consider therapy modification

Primidone: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Management: Use of alternative, nonhormonal contraceptives is recommended. Consider therapy modification

Ranolazine: May increase the serum concentration of P-glycoprotein/ABCB1 Substrates. Monitor therapy

Retinoic Acid Derivatives: May diminish the therapeutic effect of Progestins (Contraceptive). Retinoic Acid Derivatives may decrease the serum concentration of Progestins (Contraceptive). Management: Two forms of effective contraception should be used in patients receiving retinoic acid derivatives. Microdosed progesterone-only preparations (ie, minipills that do not contain estrogen) are considered an inadequate method of contraception. Exceptions: Adapalene; Alitretinoin (Topical); Bexarotene (Topical); Tretinoin (Topical). Consider therapy modification

Rifamycin Derivatives: May decrease the serum concentration of Progestins (Contraceptive). Contraceptive failure is possible. Management: Contraceptive failure is possible. Use of an alternative, nonhormonal contraceptive is recommended. Consider therapy modification

ROPINIRole: Estrogen Derivatives may increase the serum concentration of ROPINIRole. Monitor therapy

Saquinavir: May decrease the serum concentration of Progestins (Contraceptive). Management: Use an alternative or additional method of contraception due to possibly decreased contraceptive effectiveness. Injected depot medroxyprogesterone acetate does not appear to participate in this interaction. Consider therapy modification

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

Selegiline: Progestins (Contraceptive) may increase the serum concentration of Selegiline. Monitor therapy

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

Somatropin: Estrogen Derivatives may diminish the therapeutic effect of Somatropin. Shown to be a concern with oral hormone replacement therapy in postmenopausal women. Management: Monitor for reduced growth hormone efficacy. A larger somatropin dose may be required to reach treatment goal. This interaction does not appear to apply to non-orally administered estrogens (e.g., transdermal, vaginal ring). Consider therapy modification

St John's Wort: May diminish the therapeutic effect of Progestins (Contraceptive). Contraceptive failure is possible. Management: Consider using a product other than St John's wort. Contraceptive failure is possible. Use of an alternative, nonhormonal contraceptive is recommended. Consider therapy modification

Succinylcholine: Estrogen Derivatives may increase the serum concentration of Succinylcholine. Monitor therapy

Sugammadex: May decrease the serum concentration of Progestins (Contraceptive). Management: Patients receiving any hormonal contraceptive (oral or non-oral) should use an additional, nonhormonal contraceptive method during and for 7 days following sugammadex treatment. Consider therapy modification

Tazemetostat: May decrease the serum concentration of Hormonal Contraceptives. Management: Women of reproductive potential should use a non-hormonal contraceptive method during treatment with tazemetostat and for 6 months after. Men with female partners should use contraception during treatment and for 3 months after. Consider therapy modification

Tetrahydrocannabinol and Cannabidiol: May decrease the serum concentration of Hormonal Contraceptives. Management: Women using hormonal contraceptives should consider adding a barrier contraceptive due to the potential for tetrahydrocannabinol and cannabidiol to decrease concentrations and effectiveness of hormonal contraceptives. Consider therapy modification

Thalidomide: Progestins (Contraceptive) may enhance the thrombogenic effect of Thalidomide. Monitor therapy

Thalidomide: Estrogen Derivatives may enhance the thrombogenic effect of Thalidomide. Monitor therapy

Theophylline Derivatives: CYP1A2 Inhibitors (Weak) may increase the serum concentration of Theophylline Derivatives. Exceptions: Dyphylline. Monitor therapy

Thyroid Products: Estrogen Derivatives may diminish the therapeutic effect of Thyroid Products. Monitor therapy

Tipranavir: Estrogen Derivatives may enhance the dermatologic adverse effect of Tipranavir. The combination of tipranavir/ritonavir and ethinyl estradiol/norethindrone was associated with a high incidence of skin rash. Tipranavir may decrease the serum concentration of Estrogen Derivatives. Management: Women using hormonal contraceptives should consider alternative, non-hormonal forms of contraception. Consider therapy modification

Tipranavir: May increase the serum concentration of Progestins (Contraceptive). Management: Use an alternative or additional method of contraception due to possibly decreased contraceptive effectiveness. Injected depot medroxyprogesterone acetate does not appear to participate in this interaction. Consider therapy modification

TiZANidine: CYP1A2 Inhibitors (Weak) may increase the serum concentration of TiZANidine. Management: Avoid these combinations when possible. If combined use is necessary, initiate tizanidine at an adult dose of 2 mg and increase in 2 to 4 mg increments based on patient response. Monitor for increased effects of tizanidine, including adverse reactions. Consider therapy modification

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

Topiramate: May decrease the serum concentration of Progestins (Contraceptive). Management: Caution patients that this combination may be associated with reduced contraceptive effectiveness. Consider adding an additional (non-hormonal) contraceptive method. Consider therapy modification

Tranexamic Acid: Progestins (Contraceptive) may enhance the thrombogenic effect of Tranexamic Acid. Avoid combination

Triazolam: Hormonal Contraceptives may increase the serum concentration of Triazolam. Monitor therapy

Ulipristal: Progestins may diminish the therapeutic effect of Ulipristal. Ulipristal may diminish the therapeutic effect of Progestins. Management: Ulipristal for uterine fibroids (Canadian indication): avoid progestins within 12 days of stopping ulipristal; as emergency contraceptive (U.S. indication): avoid progestins within 5 days of stopping ulipristal. Avoid combination

Ursodiol: Estrogen Derivatives may diminish the therapeutic effect of Ursodiol. Monitor therapy

Vitamin K Antagonists (eg, warfarin): Progestins (Contraceptive) may diminish the anticoagulant effect of Vitamin K Antagonists. In contrast, enhanced anticoagulant effects have also been noted with some products. Management: When possible, concomitant hormonal contraceptives and coumarin derivatives should be avoided in order to eliminate the risk of thromboembolic disorders. Consider using an alternative, nonhormonal contraceptive. Consider therapy modification

Voriconazole: May increase the serum concentration of Progestins (Contraceptive). Progestins (Contraceptive) may increase the serum concentration of Voriconazole. Monitor therapy

Test Interactions

Reduced response to metyrapone test.

Adverse Reactions

>10%:

Central nervous system: Headache (23%)

Gastrointestinal: Abdominal pain (12%)

Genitourinary: Mastalgia (16%)

Neuromuscular & skeletal: Back pain (12%)

Respiratory: Upper respiratory tract infection (21%), flu-like symptoms (11%)

1% to 10%:

Central nervous system: Fatigue (6%), pain (6%), depression (5%), dizziness (5%)

Gastrointestinal: Nausea (6%), flatulence (5%)

Genitourinary: Vaginal hemorrhage (9%), dysmenorrhea (8%), vaginitis (7%)

Infection: Viral infection (6%)

Neuromuscular & skeletal: Arthralgia (9%), myalgia (5%)

Respiratory: Sinusitis (8%), pharyngitis (7%), cough (5%)

Warnings/Precautions

Concerns related to adverse effects:

  • Breast cancer: [US Boxed Warning]: Based on data from the Women’s Health Initiative (WHI) studies, an increased risk of invasive breast cancer was observed in postmenopausal women using conjugated estrogens (CE) in combination with medroxyprogesterone acetate (MPA). Observational studies noted this risk declines once therapy is discontinued. The WHI study did not observe an increased risk of invasive breast cancer in women with a hysterectomy using CE alone. The risk of breast cancer in postmenopausal patients on hormone therapy may depend upon type of estrogen and/or progestin, dose, timing of therapy initiation, duration of therapy, route of administration, and individual patient characteristics (AACE/ACE [Cobin 2017]; NAMS 2017). Hormone therapy may be associated with increased breast density (NAMS 2017); an increase in abnormal mammogram findings requiring further evaluation has been reported with estrogen alone or in combination with progestin therapy. Estrogen use may lead to severe hypercalcemia in patients with breast cancer and bone metastases; discontinue estrogen if hypercalcemia occurs.
  • Dementia: [US Boxed Warning]: Estrogens with or without progestin should not be used to prevent dementia. In the Women’s Health Initiative Memory Study (WHIMS), an increased incidence of probable dementia was observed in women ≥65 years of age taking CE alone or in combination with MPA. Because the WHI memory studies were conducted in women ≥65 years of age, it is unknown if these findings apply to younger postmenopausal women. However, hormone therapy is not recommended at any age to prevent or treat cognitive decline or dementia (AACE [Goodman 2011]; NAMS 2017).
  • Endometrial cancer: The use of unopposed estrogen in women with a uterus is associated with an increased risk of endometrial cancer. The addition of a progestin to estrogen therapy may decrease the risk of endometrial hyperplasia, a precursor to endometrial cancer. Adequate diagnostic measures, including endometrial sampling if indicated, should be performed to rule out malignancy in postmenopausal women with undiagnosed abnormal vaginal bleeding. There is no evidence that the use of natural estrogens results in a different endometrial risk profile than synthetic estrogens at equivalent estrogen doses. The risk of endometrial cancer appears to be dose and duration dependent, greatest with use ≥5 years, and may persist following discontinuation of therapy. The use of a progestin is not generally required when low doses of estrogen are used locally for vaginal atrophy, although long-term data (>1 year) supporting this recommendation are lacking (NAMS 2013; NAMS 2017).
  • Endometriosis: Estrogens may exacerbate endometriosis. Malignant transformation of residual endometrial implants has been reported posthysterectomy with unopposed estrogen therapy. Consider adding a progestin in women with residual endometriosis posthysterectomy.
  • Inherited thrombophilia: Women with inherited thrombophilias (eg, protein C or S deficiency) may have increased risk of venous thromboembolism (DeSancho 2010; van Vlijmen 2011).
  • Lipid effects: Estrogen compounds are generally associated with lipid effects such as increased HDL-cholesterol and decreased LDL-cholesterol. Triglycerides may also be increased in women with preexisting hypertriglyceridemia; discontinue if pancreatitis occurs.
  • Ovarian cancer: Available information related to the use of menopausal estrogen or estrogen/progestin therapy and risk of ovarian cancer is inconsistent. If an association is present, the absolute risk is likely rare and may be influenced by duration of therapy (AACE [Goodman 2011]; ES [Stuenkel 2015]; NAMS 2017).
  • Retinal vascular thrombosis: Estrogens may cause retinal vascular thrombosis; discontinue if migraine, loss of vision, proptosis, diplopia, or other visual disturbances occur; discontinue permanently if papilledema or retinal vascular lesions are observed on examination.

Disease-related concerns:

  • Asthma: Use caution in patients with asthma; may exacerbate disease.
  • Carbohydrate intolerance: May impair glucose tolerance; use caution in patients with diabetes. Prior to therapy, consider age, cardiovascular and metabolic risk factors in patients previously diagnosed with diabetes (AACE/ACE [Cobin 2017]).
  • Cardiovascular disease: [US Boxed Warning]: Estrogens with or without progestin should not be used to prevent cardiovascular disease. Using data from the Women’s Health Initiative (WHI) studies, an increased risk of deep vein thrombosis (DVT) and stroke has been reported with CE and an increased risk of DVT, stroke, pulmonary emboli (PE), and myocardial infarction (MI) has been reported with CE with MPA in postmenopausal women 50 to 79 years of age. Additional risk factors include diabetes mellitus, hypercholesterolemia, hypertension, SLE, obesity, tobacco use, and/or history of venous thromboembolism (VTE). Risk factors should be managed appropriately; discontinue use immediately if adverse cardiovascular events occur or are suspected. Due to possible lower risk of thrombotic events, transdermal administration may be preferred for treating vasomotor symptoms of menopause in patients with risk factors for cardiovascular disease (AACE/ACE [Cobin 2017]; ACOG 556 2013; ES [Stuenkel 2015]). Use is contraindicated in women with active DVT, PE, arterial thromboembolic disease (stroke and MI), or a history of these conditions.
  • Diseases exacerbated by fluid retention: Use with caution in patients with diseases which may be exacerbated by fluid retention, including cardiac or renal dysfunction.
  • Epilepsy: Use caution with epilepsy; may exacerbate disease.
  • Gallbladder disease: Use of postmenopausal estrogen may be associated with an increased risk of gallbladder disease requiring surgery.
  • Hepatic dysfunction: Estrogens are poorly metabolized in patients with hepatic dysfunction. Use caution with a history of cholestatic jaundice associated with prior estrogen use or pregnancy. Discontinue if jaundice develops or if acute or chronic hepatic disturbances occur. Use is contraindicated with hepatic impairment or disease.
  • Hepatic hemangiomas: Use with caution in patients with hepatic hemangiomas; may exacerbate disease.
  • Hereditary angioedema: Exogenous estrogens may exacerbate angioedema symptoms in women with hereditary angioedema.
  • Hypoparathyroidism: Use caution with hypoparathyroidism; estrogen-induced hypocalcemia may occur.
  • Migraine: Use caution with migraine; may exacerbate disease.
  • Porphyria: Use with caution in patients with porphyria; may exacerbate disease.
  • SLE: Use with caution in patients with SLE; may exacerbate disease.

Concurrent drug therapy issues:

  • Drug-drug interactions: 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.
  • Thyroid replacement therapy: Estrogens may increase thyroid-binding globulin (TBG) levels leading to increased circulating total thyroid hormone levels. Women on thyroid replacement therapy may require higher doses of thyroid hormone while receiving estrogens.

Special populations:

  • Premenopausal women: Not for use prior to menopause.
  • Surgical patients: Whenever possible, should be discontinued at least 4 to 6 weeks prior to elective surgery associated with an increased risk of thromboembolism or during periods of prolonged immobilization.

Other warnings/precautions:

  • Duration of use: Extended use of menopausal hormone therapy may be considered for persistent vasomotor symptoms, issues related to quality of life, or for osteoporosis prevention in women at increased risk of fracture. Menopausal hormonal therapy does not need to be routinely discontinued in women >60 years of age and may continue in women >65 years of age after clinical evaluation and discussion of benefits and risks of treatment. Annual exams should be performed with a review of comorbidities; possible adjustments to safer lower-dose and/or route of administration should be discussed (ACOG 565 2013; NAMS 2017).
  • Genitourinary syndrome of menopause: Low-dose vaginal estrogen is preferred over systemic therapy for genitourinary syndrome of menopause (GSM) in the absence of vasomotor symptoms due to increased efficacy and decreased systemic effects (eg, cardiovascular effects, cancer risk) (Crandall 2018; NAMS 2013; NAMS 2017).
  • Laboratory changes: The use of estrogens and/or progestins may change the results of some laboratory tests (eg, coagulation factors, lipids, glucose tolerance, binding proteins). The dose, route, and the specific estrogen/progestin influences these changes.
  • Osteoporosis use: In women with premature menopause, hormone therapy to prevent bone loss may be used unless otherwise contraindicated; therapy should be reassessed when the average age of menopause is reached. It is also an appropriate bone-active therapy for women with vasomotor symptoms who are <60 years of age or within 10 years of menopause onset. Use may be considered for women at high risk of fractures who are not candidates for other osteoporosis therapies (NAMS 2017).
  • Risks vs benefits: When used for the relief of menopausal symptoms or increased risk of bone fracture/loss, the benefit-risk of hormone therapy is most favorable if started in patients who have no contraindications to therapy, are <60 years of age, within 10 years of menopause onset, have a favorable lipid profile, and do not have the factor V Leiden genotype or metabolic syndrome. Risk factors for cardiovascular disease should also be considered when evaluating therapy and route of administration (AACE/ACE [Cobin 2017]; NAMS 2017). [US Boxed Warning]: Estrogens with or without progestin should be used for the shortest duration possible at the lowest effective dose consistent with treatment goals and risks for the individual woman. Patients should be reevaluated as clinically appropriate to determine if treatment is still necessary. Available data related to treatment risks are from Women’s Health Initiative (WHI) studies, which evaluated oral CE 0.625 mg with or without MPA 2.5 mg relative to placebo in postmenopausal women. Other combinations and dosage forms of estrogens and progestins were not studied. Outcomes reported from clinical trials using CE with or without MPA should be assumed to be similar for other doses and other dosage forms of estrogens and progestins until comparable data becomes available.

Monitoring Parameters

Prior to therapy, baseline risk for breast cancer and CVD. During therapy, age appropriate breast and pelvic exams; blood pressure; unscheduled bleeding lasting >6 months for endometrial pathology (sooner in patients who are obese, diabetic, or have a history of endometrial cancer); serum triglycerides (2 weeks after starting therapy in patients with baseline level >200 mg/dL); TSH (6 to 12 weeks after starting oral therapy in patients taking thyroid replacement) (ES [Stuenkel 2015]).

Menopausal symptoms: Efficacy beginning 1 to 3 months after starting therapy, then every 6 to 12 months as appropriate. Duration of treatment should be evaluated at least annually (ES [Stuenkel 2015]).

Note: Monitoring of FSH and serum estradiol is not useful when managing vasomotor symptoms or GSM.

Prevention of osteoporosis: Bone density measurement

Pregnancy

Pregnancy Considerations

Use is contraindicated in pregnant women.

In general, the use of estrogen and progestin as in combination hormonal contraceptives has not been associated with teratogenic effects when inadvertently taken early in pregnancy.

Patient Education

  • Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
  • Patient may experience back pain, passing gas, hair loss, cramps, bloating, muscle pain, joint pain, tender breasts, flu-like symptoms, common cold symptoms, enlarged breasts, or dark spots on face. Have patient report immediately to prescriber signs of liver problems (dark urine, fatigue, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin), signs of gallstones (pain in the upper right abdominal area, right shoulder area, or between the shoulder blades; yellow skin; or fever with chills), signs of severe cerebrovascular disease (change in strength on one side is greater than the other, difficulty speaking or thinking, change in balance, or vision changes), signs of blood clots (numbness or weakness on one side of the body; pain, redness, tenderness, warmth, or swelling in the arms or legs; change in color of an arm or leg; chest pain; shortness of breath; fast heartbeat; or coughing up blood), severe abdominal pain, blindness, severe loss of strength and energy, edema, severe headache, severe nausea, vomiting, severe dizziness, passing out, vision changes, bulging eyes, contact lens discomfort, lump in breast, breast soreness or pain, nipple discharge, vaginal pain, itching, and discharge, abnormal vaginal bleeding, depression, or trouble with memory (HCAHPS).
  • Educate patient about signs of a significant reaction (eg, 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. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.

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