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Acetaminophen and Codeine

Generic name: acetaminophen/codeine systemic

Brand names: Aceta w/ Codeine, Capital w/Codeine, EZ III, Phenaphen with Codeine, Tylenol with Codeine, Capital with Codeine Suspension, Tylenol with Codeine #2, Tylenol with Codeine #3, Tylenol with Codeine #4, Cocet, Cocet Plus, Codrix, Tylenol with Codeine #1

Boxed Warning

Risk of medication errors (oral solution or suspension):

Ensure accuracy when prescribing, dispensing, and administering acetaminophen/codeine oral solution or suspension. Dosing errors due to confusion between mg and mL and other codeine-containing oral products of different concentrations can result in accidental overdose and death.

Addiction, abuse, and misuse:

Acetaminophen/codeine exposes patient and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Assess each patient's risk prior to prescribing acetaminophen/codeine, and monitor all patients regularly for the development of these behaviors or conditions.

Opioid analgesic risk evaluation and mitigation strategy (REMS)

To ensure that the benefits of opioid analgesics outweigh the risks of addiction, abuse, and misuse, the Food and Drug Administration (FDA) has required a REMS for these products. Under the requirements of the REMS, drug companies with approved opioid analgesic products must make REMS-compliant education programs available to health care providers. Health care providers are strongly encouraged to complete a REMS-compliant education program; counsel patients and/or their caregivers, with every prescription, on safe use, serious risks, storage, and disposal of these products; emphasize to patients and their caregivers the importance of reading the Medication Guide every time it is provided by their pharmacist; and consider other tools to improve patient, household, and community safety.

Life-threatening respiratory depression:

Serious, life-threatening, or fatal respiratory depression may occur with use of acetaminophen/codeine. Monitor for respiratory depression, especially during initiation of acetaminophen/codeine or following a dose increase.

Accidental ingestion:

Accidental ingestion of even one dose of acetaminophen/codeine, especially by children, can result in a fatal overdose of codeine.

Ultra-rapid metabolism of codeine and other risk factors for life-threatening respiratory depression in children:

Life-threatening respiratory depression and death have occurred in children who received codeine. Most of the reported cases occurred following tonsillectomy and/or adenoidectomy, and many of the children had evidence of being ultra-rapid metabolizers of codeine due to a CYP450 2D6 polymorphism. Acetaminophen/codeine is contraindicated in pediatric patients <12 years of age and in pediatric patients <18 years of age following tonsillectomy and/or adenoidectomy. Avoid the use of acetaminophen/codeine in pediatric patients 12 to 18 years of age who have other risk factors that may increase their sensitivity to the respiratory depressant effects of codeine.

Neonatal opioid withdrawal syndrome:

Prolonged use of acetaminophen/codeine during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.

Hepatotoxicity:

Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death. Most of the cases of liver injury are associated with the use of acetaminophen at dosages that exceed 4 g/day, and often involve more than one acetaminophen-containing product.

Interactions with drugs affecting CYP-450 isoenzyme:

The effects of concomitant use or discontinuation of CYP450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complex. Use of CYP450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with acetaminophen/codeine requires careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine.

Risks from concomitant use with benzodiazepines or other CNS depressants:

Concomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of acetaminophen/codeine and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation.

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Solution, Oral:

Generic: Acetaminophen 120 mg and codeine phosphate 12 mg per 5 mL (5 mL, 12.5 mL, 118 mL, 473 mL)

Suspension, Oral:

Capital/Codeine: Acetaminophen 120 mg and codeine phosphate 12 mg per 5 mL (473 mL [DSC]) [fruit punch flavor]

Tablet, Oral:

Tylenol with Codeine #3: Acetaminophen 300 mg and codeine phosphate 30 mg [contains corn starch, sodium metabisulfite]

Tylenol with Codeine #4: Acetaminophen 300 mg and codeine phosphate 60 mg [contains corn starch, sodium metabisulfite]

Generic: Acetaminophen 300 mg and codeine phosphate 15 mg, Acetaminophen 300 mg and codeine phosphate 30 mg, Acetaminophen 300 mg and codeine phosphate 60 mg

Pharmacology

Mechanism of Action

Acetaminophen: Although not fully elucidated, the analgesic effects are believed to be due to activation of descending serotonergic inhibitory pathways in the CNS. Interactions with other nociceptive systems may be involved as well (Smith 2009). Antipyresis is produced from inhibition of the hypothalamic heat-regulating center.

Codeine: Binds to opiate receptors in the CNS, causing inhibition of ascending pain pathways, altering the perception of and response to pain; causes cough suppression by direct central action in the medulla; produces generalized CNS depression.

Use: Labeled Indications

Pain management: Management of mild to moderate pain where treatment with an opioid is appropriate and for which alternative treatments are inadequate.

Limitations of use: Reserve for use in patients for whom alternative treatment options (eg, nonopioid analgesics) are ineffective, not tolerated, or would be otherwise inadequate.

Contraindications

Hypersensitivity (eg, anaphylaxis) to acetaminophen, codeine, or any component of the formulation; pediatric patients <12 years of age; postoperative management in pediatric patients <18 years of age who have undergone tonsillectomy and/or adenoidectomy; significant respiratory depression; acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment; GI obstruction, including paralytic ileus (known or suspected); concurrent use with or within 14 days following monoamine oxidase inhibitors (MAOIs) therapy.

Canadian labeling: Additional contraindications (not in US labeling): Hypersensitivity to other opioid analgesics; mechanical GI obstruction (eg, bowel obstruction, strictures) or any disease/condition that affects bowel transit (known or suspected); suspected surgical abdomen (eg, acute appendicitis, pancreatitis); mild pain that can be managed with other pain medications; severe hepatic or renal impairment; acute or severe bronchial asthma, chronic obstructive airway disease; status asthmaticus; hypercapnia; cor pulmonale; acute alcoholism; delirium tremens; seizure disorder; severe CNS depression; increased cerebrospinal or intracranial pressure; head injury; pregnancy; use during labor and delivery; CYP2D6 ultra-rapid metabolizers. Some products may contraindicate use in patients <18 years (refer to specific product labeling).

Documentation of allergenic cross-reactivity for opioids is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.

Dosage and Administration

Dosing: Adult

Note: Adult doses ≥60 mg codeine fail to give commensurate relief of pain but merely prolong analgesia and are associated with an appreciably increased incidence of side effects.

Pain management: Oral:

Solution or suspension:

Acetaminophen 120 mg/codeine 12 mg per 5 mL: 15 mL every 4 hours as needed; adjust dose according to severity of pain and response of patient (maximum: acetaminophen 4,000 mg per 24 hours).

Acetaminophen 160 mg/codeine 8 mg per 5 mL [Canadian product]: 10 to 20 mL every 4 hours as needed; adjust dose according to severity of pain and response of patient (maximum: 100 mL per 24 hours)

Tablets: Acetaminophen (300 to 1,000 mg/dose)/codeine (15 to 60 mg/dose) every 4 hours as needed; adjust dose according to severity of pain and response of patient (maximum: acetaminophen 4,000 mg/codeine 360 mg per 24 hours).

Discontinuation of therapy: When discontinuing chronic opioid therapy, the dose should be gradually tapered down. An optimal universal tapering schedule for all patients has not been established (CDC [Dowell 2016]). Proposed schedules range from slow (eg, 10% reductions per week) to rapid (eg, 25% to 50% reduction every few days) (CDC 2015). Tapering schedules should be individualized to minimize opioid withdrawal while considering patient-specific goals and concerns as well as the pharmacokinetics of the opioid being tapered. An even slower taper may be appropriate in patients who have been receiving opioids for a long duration (eg, years), particularly in the final stage of tapering, whereas more rapid tapers may be appropriate in patients experiencing severe adverse events (CDC [Dowell 2016]). Monitor carefully for signs/symptoms of withdrawal. If the patient displays withdrawal symptoms, consider slowing the taper schedule; alterations may include increasing the interval between dose reductions, decreasing amount of daily dose reduction, pausing the taper and restarting when the patient is ready, and/or coadministration of an alpha2 agonist (eg, clonidine) to blunt withdrawal symptoms (Berna 2015; CDC [Dowell 2016]). Continue to offer nonopioid analgesics as needed for pain management during the taper; consider nonopioid adjunctive treatments for withdrawal symptoms (eg GI complaints, muscle spasm) as needed (Berna 2015; Sevarino 2018).

Dosing: Geriatric

Refer to adult dosing. Use with caution and consider initiation at the low end of the dosing range; titrate slowly.

Dosing: Pediatric

Note: Doses should be titrated to appropriate analgesic effect. All sources of acetaminophen (eg, prescription, OTC, combination products) should be considered when evaluating a patient's maximum daily dose. To lower the risk for hepatotoxicity, limit daily dose to ≤75 mg/kg/day (maximum of 5 daily doses), not to exceed 4,000 mg/day; while recommended doses are generally considered safe, hepatotoxicity has been reported (rarely) even with doses below recommendations (AAP [Sullivan 2011]; Heard 2014; Lavonas 2010).

Pain management, mild to moderate:

Note: Use is contraindicated in pediatric patients <12 years of age and for postoperative management in pediatric patients 12 to 18 years of age who have undergone tonsillectomy and/or adenoidectomy. Avoid codeine use in all pediatric patient populations in which it is contraindicated and in pediatric patients 12 to 18 years of age who have other risk factors that increase risk for respiratory depression associated with codeine (eg, conditions associated with hypoventilation like postoperative status, obstructive sleep apnea, obesity, severe pulmonary disease, neuromuscular disease, use of other medications known to depress respiratory drive); in rare cases in which codeine-containing product is the only option, consider genotype testing prior to use; use extra precaution; monitor closely for adverse effects. Codeine has been associated with reports of life-threatening or fatal respiratory depression in children and adolescents; multifactorial causes have been identified; of primary concern are unrecognized ultrarapid metabolizers of CYP2D6 who may have extensive conversion of codeine (prodrug) to morphine and thus increased opioid-mediated effects (AAP [Tobias 2016]; Dancel 2017; Gammal 2016; Goldschneider 2017; Poonai 2015).

Children and Adolescents: Limited data available in ages <12 years and in postoperative tonsillectomy and/or adenoidectomy patients: Not a preferred agent; use only when determined codeine is only option

Weight-directed dosing: Dosage for individual components:

Codeine: Oral: 0.5 to 1 mg/kg/dose every 4 to 6 hours; maximum dose: 60 mg/dose (APS 2016). Note: Do not use for postoperative tonsillectomy and/or adenoidectomy pain management

Acetaminophen: Oral: 10 to 15 mg/kg/dose every 4 to 6 hours; do not exceed 5 doses in 24 hours; maximum daily dose: 75 mg/kg/day not to exceed 4,000 mg/day

Acetaminophen 160 mg/codeine 8 mg per 5 mL [Canadian product]: Children ≥12 years and Adolescents: Oral: 10 to 20 mL every 4 to 6 hours as needed; adjust dose according to severity of pain and response of patient; maximum daily dose: 100 mL/24 hours

Administration

Oral solution or suspension: Administer with an accurate measuring device (calibrated oral syringe or measuring cup); do not use a household teaspoon or tablespoon to measure dose (overdosage may occur). Shake suspension well before administering dose.

Storage

Store at 20°C to 25°C (68°F to 77°F); protect from light.

Acetaminophen and Codeine Images

Drug Interactions

Abiraterone Acetate: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Management: Avoid concurrent use of abiraterone with CYP2D6 substrates that have a narrow therapeutic index whenever possible. When concurrent use is not avoidable, monitor patients closely for signs/symptoms of toxicity. Consider therapy modification

Ajmaline: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Alizapride: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Alvimopan: Opioid Agonists may enhance the adverse/toxic effect of Alvimopan. This is most notable for patients receiving long-term (i.e., more than 7 days) opiates prior to alvimopan initiation. Management: Alvimopan is contraindicated in patients receiving therapeutic doses of opioids for more than 7 consecutive days immediately prior to alvimopan initiation. Consider therapy modification

Amphetamines: May enhance the analgesic effect of Opioid Agonists. Monitor therapy

Anticholinergic Agents: May enhance the adverse/toxic effect of Opioid Agonists. Specifically, the risk for constipation and urinary retention may be increased with this combination. Monitor therapy

Asunaprevir: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Consider therapy modification

Azelastine (Nasal): CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). Avoid combination

Blonanserin: CNS Depressants may enhance the CNS depressant effect of Blonanserin. Consider therapy modification

Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Bromopride: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Bromperidol: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

Busulfan: Acetaminophen may increase the serum concentration of Busulfan. Monitor therapy

Cannabidiol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Cannabis: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

CarBAMazepine: May increase the metabolism of Acetaminophen. This may 1) diminish the effect of acetaminophen; and 2) increase the risk of liver damage. Monitor therapy

Chlormethiazole: May enhance the CNS depressant effect of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Consider therapy modification

Chlorphenesin Carbamate: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

CNS Depressants: May enhance the CNS depressant effect of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Cobicistat: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

CYP2D6 Inhibitors (Moderate): May diminish the therapeutic effect of Codeine. These CYP2D6 inhibitors may prevent the metabolic conversion of codeine to its active metabolite morphine. Monitor therapy

CYP2D6 Inhibitors (Strong): May diminish the therapeutic effect of Codeine. These CYP2D6 inhibitors may prevent the metabolic conversion of codeine to its active metabolite morphine. Consider therapy modification

CYP3A4 Inducers (Moderate): May decrease serum concentrations of the active metabolite(s) of Codeine. Monitor therapy

CYP3A4 Inducers (Strong): May decrease serum concentrations of the active metabolite(s) of Codeine. Monitor therapy

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

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

Dacomitinib: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Management: Avoid concurrent use of dacomitinib with CYP2D6 subtrates that have a narrow therapeutic index. Consider therapy modification

Dapsone (Topical): May enhance the adverse/toxic effect of Methemoglobinemia Associated Agents. Monitor therapy

Darunavir: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Dasatinib: Acetaminophen may enhance the hepatotoxic effect of Dasatinib. Dasatinib may increase the serum concentration of Acetaminophen. Consider therapy modification

Desmopressin: Opioid Agonists may enhance the adverse/toxic effect of Desmopressin. Monitor therapy

Dimethindene (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Diuretics: Opioid Agonists may enhance the adverse/toxic effect of Diuretics. Opioid Agonists may diminish the therapeutic effect of Diuretics. Monitor therapy

Dronabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (eg, opioids, barbiturates) with concomitant use. Exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Consider therapy modification

Eluxadoline: Opioid Agonists may enhance the constipating effect of Eluxadoline. Avoid combination

Flucloxacillin: May enhance the adverse/toxic effect of Acetaminophen. Specifically, the risk for high anion gap metabolic acidosis may be increased. Monitor therapy

Flunitrazepam: CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. Consider therapy modification

Fosphenytoin-Phenytoin: May decrease the serum concentration of Acetaminophen. Specifically, serum concentrations of acetaminophen may be decreased (leading to decreased efficacy), but the formation of the toxic N-acetyl-p-benzoquinone imine (NAPQI) metabolite may be increased (leading to increased hepatotoxicity). Monitor therapy

Gastrointestinal Agents (Prokinetic): Opioid Agonists may diminish the therapeutic effect of Gastrointestinal Agents (Prokinetic). Monitor therapy

HYDROcodone: CNS Depressants may enhance the CNS depressant effect of HYDROcodone. Management: Avoid concomitant use of hydrocodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Imatinib: Acetaminophen may enhance the hepatotoxic effect of Imatinib. Monitor therapy

Isoniazid: May enhance the adverse/toxic effect of Acetaminophen. Monitor therapy

Kava Kava: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Lemborexant: May enhance the CNS depressant effect of CNS Depressants. Management: Dosage adjustments of lemborexant and of concomitant CNS depressants may be necessary when administered together because of potentially additive CNS depressant effects. Close monitoring for CNS depressant effects is necessary. Consider therapy modification

Local Anesthetics: Methemoglobinemia Associated Agents may enhance the adverse/toxic effect of Local Anesthetics. Specifically, the risk for methemoglobinemia may be increased. Monitor therapy

Lofexidine: May enhance the CNS depressant effect of CNS Depressants. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Monitor therapy

Lumefantrine: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Methotrimeprazine: CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. Consider therapy modification

MetyraPONE: May increase the serum concentration of Acetaminophen. More importantly, by inhibiting the conjugative metabolism of acetaminophen, metyrapone may shift the metabolism towards the oxidative route that produces a hepatotoxic metabolite. Monitor therapy

MetyroSINE: CNS Depressants may enhance the sedative effect of MetyroSINE. Monitor therapy

Minocycline (Systemic): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Mipomersen: Acetaminophen may enhance the hepatotoxic effect of Mipomersen. Monitor therapy

Monoamine Oxidase Inhibitors: May enhance the adverse/toxic effect of Codeine. Avoid combination

Nabilone: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Nalmefene: May diminish the therapeutic effect of Opioid Agonists. Management: Avoid the concomitant use of nalmefene and opioid agonists. Discontinue nalmefene 1 week prior to any anticipated use of opioid agonistss. If combined, larger doses of opioid agonists will likely be required. Consider therapy modification

Naltrexone: May diminish the therapeutic effect of Opioid Agonists. Management: Seek therapeutic alternatives to opioids. See full drug interaction monograph for detailed recommendations. Consider therapy modification

Nitric Oxide: May enhance the adverse/toxic effect of Methemoglobinemia Associated Agents. Combinations of these agents may increase the likelihood of significant methemoglobinemia. Monitor therapy

Opioid Agonists: CNS Depressants may enhance the CNS depressant effect of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Opioids (Mixed Agonist / Antagonist): May diminish the analgesic effect of Opioid Agonists. Management: Seek alternatives to mixed agonist/antagonist opioids in patients receiving pure opioid agonists, and monitor for symptoms of therapeutic failure/high dose requirements (or withdrawal in opioid-dependent patients) if patients receive these combinations. Avoid combination

Orphenadrine: CNS Depressants may enhance the CNS depressant effect of Orphenadrine. Avoid combination

Oxomemazine: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

OxyCODONE: CNS Depressants may enhance the CNS depressant effect of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Panobinostat: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Avoid combination

Peginterferon Alfa-2b: May decrease the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Peginterferon Alfa-2b may increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Pegvisomant: Opioid Agonists may diminish the therapeutic effect of Pegvisomant. Monitor therapy

Perampanel: May enhance the CNS depressant effect of CNS Depressants. Management: Patients taking perampanel with any other drug that has CNS depressant activities should avoid complex and high-risk activities, particularly those such as driving that require alertness and coordination, until they have experience using the combination. Consider therapy modification

Perhexiline: CYP2D6 Substrates (High risk with Inhibitors) may increase the serum concentration of Perhexiline. Perhexiline may increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

PHENobarbital: May enhance the CNS depressant effect of Codeine. PHENobarbital may decrease the serum concentration of Codeine. Management: Avoid use of codeine and phenobarbital when possible. Monitor for respiratory depression/sedation. Because phenobarbital is also a strong CYP3A4 inducer, monitor for decreased codeine efficacy and withdrawal if combined. Consider therapy modification

Phenylephrine (Systemic): Acetaminophen may increase the serum concentration of Phenylephrine (Systemic). Monitor therapy

Piribedil: CNS Depressants may enhance the CNS depressant effect of Piribedil. Monitor therapy

Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Monitor therapy

Prilocaine: Methemoglobinemia Associated Agents may enhance the adverse/toxic effect of Prilocaine. Combinations of these agents may increase the likelihood of significant methemoglobinemia. Management: Monitor patients for signs of methemoglobinemia (e.g., hypoxia, cyanosis) when prilocaine is used in combination with other agents associated with development of methemoglobinemia. Avoid lidocaine/prilocaine in infants receiving such agents. Monitor therapy

Primidone: May enhance the CNS depressant effect of Codeine. Primidone may decrease the serum concentration of Codeine. Management: Avoid use of codeine and primidone when possible. Monitor for respiratory depression/sedation. Because primidone is also a strong CYP3A4 inducer, monitor for decreased codeine efficacy and withdrawal if combined. Consider therapy modification

Probenecid: May increase the serum concentration of Acetaminophen. Probenecid may also limit the formation of at least one major non-toxic metabolite, possibly increasing the potential for formation of the toxic NAPQI metabolite. Consider therapy modification

QuiNINE: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Ramosetron: Opioid Agonists may enhance the constipating effect of Ramosetron. Monitor therapy

ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Monitor therapy

Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Monitor therapy

Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Monitor therapy

Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Monitor therapy

Serotonergic Agents (High Risk): Opioid Agonists may enhance the serotonergic effect of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Monitor therapy

Sincalide: Drugs that Affect Gallbladder Function may diminish the therapeutic effect of Sincalide. Management: Consider discontinuing drugs that may affect gallbladder motility prior to the use of sincalide to stimulate gallbladder contraction. Consider therapy modification

Sodium Nitrite: Methemoglobinemia Associated Agents may enhance the adverse/toxic effect of Sodium Nitrite. Combinations of these agents may increase the likelihood of significant methemoglobinemia. Monitor therapy

Sodium Oxybate: May enhance the CNS depressant effect of CNS Depressants. Management: Consider alternatives to combined use. When combined use is needed, consider minimizing doses of one or more drugs. Use of sodium oxybate with alcohol or sedative hypnotics is contraindicated. Consider therapy modification

Somatostatin Analogs: May decrease the metabolism of Codeine. The formation of two major codeine metabolites (morphine and norcodeine) may be impaired by somatostatin analogs. Monitor therapy

SORAfenib: Acetaminophen may enhance the hepatotoxic effect of SORAfenib. SORAfenib may increase the serum concentration of Acetaminophen. Consider therapy modification

Succinylcholine: May enhance the bradycardic effect of Opioid Agonists. Monitor therapy

Suvorexant: CNS Depressants may enhance the CNS depressant effect of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Consider therapy modification

Tapentadol: May enhance the CNS depressant effect of CNS Depressants. Management: Avoid concomitant use of tapentadol and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Tetrahydrocannabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Tetrahydrocannabinol and Cannabidiol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Avoid combination

Vitamin K Antagonists (eg, warfarin): Acetaminophen may enhance the anticoagulant effect of Vitamin K Antagonists. This appears most likely with daily acetaminophen doses exceeding 1.3 or 2 g/day for multiple consecutive days. Monitor therapy

Zolpidem: CNS Depressants may enhance the CNS depressant effect of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Consider therapy modification

Test Interactions

See individual agents.

Adverse Reactions

Also see individual agents.

Frequency not defined:

Central nervous system: Dizziness, drowsiness, dysphoria, euphoria, sedation, serotonin syndrome

Dermatologic: Pruritus, skin rash

Endocrine & metabolic: Adrenocortical insufficiency

Gastrointestinal: Abdominal pain, constipation, nausea, vomiting

Hematologic & oncologic: Agranulocytosis, thrombocytopenia

Hypersensitivity: Hypersensitivity reaction

Respiratory: Dyspnea

<1%, postmarketing, and/or case reports: Hypogonadism (Brennan 2013; Debono 2011), respiratory depression

Warnings/Precautions

Concerns related to adverse effects:

  • CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks that require mental alertness (eg, operating machinery or driving).
  • Constipation: May cause or aggravate constipation; chronic use may result in obstructive bowel disease, particularly in those with underlying intestinal motility disorders. May also be problematic in patients with unstable angina and patients post-myocardial infarction (MI). Consider preventive measures (eg, stool softener, increased fiber) to reduce the potential for constipation.
  • Hepatotoxicity: [US Boxed Warning]: Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death. Most of the cases of liver injury are associated with the use of acetaminophen at dosages that exceed 4 g/day, and often involve more than one acetaminophen-containing product. Risk is increased with alcohol use, preexisting liver disease, and intake of more than one source of acetaminophen-containing medications. Chronic daily dosing in adults has also resulted in liver damage in some patients.
  • Hypersensitivity/anaphylactic reactions: Hypersensitivity and anaphylactic reactions have been reported with acetaminophen use; discontinue immediately if symptoms of allergic or hypersensitivity reactions occur.
  • Hypotension: May cause severe hypotension (including orthostatic hypotension and syncope); use with caution in patients with hypovolemia, cardiovascular disease (including acute MI), or drugs that may exaggerate hypotensive effects (including phenothiazines or general anesthetics). Monitor for symptoms of hypotension following initiation or dose titration. Avoid use in patients with circulatory shock.
  • Phenanthrene hypersensitivity: Use with caution in patients with hypersensitivity reactions to other phenanthrene-derivative opioid agonists (hydrocodone, hydromorphone, levorphanol, oxycodone, oxymorphone).
  • Respiratory depression: [US Boxed Warning]: Serious, life-threatening, or fatal respiratory depression may occur with use. Monitor for respiratory depression, especially during initiation of therapy or following a dose increase. Carbon dioxide retention from opioid-induced respiratory depression can exacerbate the sedating effects of opioids.
  • Skin reactions: Serious and potentially fatal skin reactions, including acute generalized exanthematous pustulosis, Stevens-Johnson syndrome, and toxic epidermal necrolysis, have occurred rarely with acetaminophen use. Discontinue therapy at the first appearance of skin rash or any other sign of hypersensitivity

Disease-related concerns:

  • Abdominal conditions: May obscure diagnosis or clinical course of patients with acute abdominal conditions.
  • Adrenocortical insufficiency: Use with caution in patients with adrenocortical insufficiency, including Addison disease. Long-term opioid use may cause secondary hypogonadism, which may lead to sexual dysfunction, infertility, mood disorders, and osteoporosis (Brennan 2013).
  • Biliary tract impairment: Use with caution in patients with biliary tract dysfunction, including acute pancreatitis; opioids may cause constriction of sphincter of Oddi.
  • CNS depression/coma: Avoid use in patients with impaired consciousness or coma as these patients are susceptible to intracranial effects of CO2 retention.
  • Delirium tremens: Use with caution in patients with delirium tremens.
  • G6PD deficiency: Use acetaminophen with caution in patients with known G6PD deficiency.
  • Head trauma: Use with extreme caution in patients with head injury, intracranial lesions, or elevated intracranial pressure (ICP); exaggerated elevation of ICP may occur.
  • Hepatic impairment: Use with caution in patients with hepatic impairment. Use with caution in patients with alcoholic liver disease; consuming ≥3 alcoholic drinks/day may increase the risk of liver damage.
  • Mental health conditions: Use opioids with caution for chronic pain in patients with mental health conditions (eg, depression, anxiety disorders, post-traumatic stress disorder) due to increased risk for opioid use disorder and overdose; more frequent monitoring is recommended (Dowell [CDC 2016]).
  • Obesity: Use with caution in patients who are morbidly obese.
  • Prostatic hyperplasia/urinary stricture: Use with caution in patients with prostatic hyperplasia and/or urinary stricture.
  • Psychosis: Use with caution in patients with toxic psychosis.
  • Renal impairment: Use with caution in patients with renal impairment.
  • Respiratory disease: Use with caution and monitor for respiratory depression in patients with significant chronic obstructive pulmonary disease or cor pulmonale, and those with a substantially decreased respiratory reserve, hypoxia, hypercapnia, or preexisting respiratory depression, particularly when initiating and titrating therapy; critical respiratory depression may occur, even at therapeutic dosages. Consider the use of alternative nonopioid analgesics in these patients.
  • Seizure disorder: Use with caution in patients with a history of seizure disorders; may cause or exacerbate seizures.
  • Sleep-related disorders: Opioid use increases the risk for sleep-related disorders (eg, central sleep apnea [CSA], hypoxemia) in a dose-dependent fashion. Use with caution for chronic pain and titrate dosage cautiously in patients with risk factors for sleep-disordered breathing (eg, heart failure, obesity). Consider dose reduction in patients presenting with CSA. Avoid opioids in patients with moderate to severe sleep-disordered breathing (Dowell [CDC 2016]).
  • Thyroid dysfunction: Use with caution in patients with thyroid dysfunction.

Concurrent drug therapy issues:

  • Benzodiazepines and other CNS depressants: [US Boxed Warning]: Concomitant use of opioids with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of acetaminophen/codeine and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation.
  • Cytochrome P450 interactions: [US Boxed Warning]: The effects of concomitant use or discontinuation of CYP-450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complex. Use of CYP-450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with acetaminophen/codeine requires careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine.
  • 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.

Special populations:

  • CYP2D6 “ultrarapid metabolizers”: Use caution in patients with ≥2 copies of the variant CYP2D6*2 allele; may have extensive conversion to morphine and thus increased opioid-mediated effects. Avoid the use of codeine in these patients; consider alternative analgesics such as morphine or a nonopioid agent (Crews 2012). The occurrence of this phenotype is seen in 0.5% to 1% of Chinese and Japanese, 0.5% to 1% of Hispanics, 1% to 10% of Caucasians, 3% of African-Americans, and 16% to 28% of North Africans, Ethiopians, and Arabs.
  • Cachectic or debilitated patients: Use with caution in cachectic or debilitated patients; there is a greater potential for critical respiratory depression, even at therapeutic dosages. Consider the use of alternative nonopioid analgesics in these patients.
  • Elderly: Use with caution in the elderly; may be more sensitive to adverse effects, such as respiratory depression. Use opioids for chronic pain with caution in this age group; monitor closely due to an increased potential for risks, including certain risks such as falls/fracture, cognitive impairment, and constipation. Clearance may also be reduced in older adults (with or without renal impairment) resulting in a narrow therapeutic window and increasing the risk for respiratory depression or overdose (Dowell [CDC 2016]). Consider the use of alternative nonopioid analgesics in these patients.
  • Neonates: Neonatal withdrawal syndrome: [US Boxed Warning]: Prolonged use during pregnancy can cause neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated according to protocols developed by neonatology experts. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available. Signs and symptoms include irritability, hyperactivity and abnormal sleep pattern, high pitched cry, tremor, vomiting, diarrhea, and failure to gain weight. Onset, duration, and severity depend on the drug used, duration of use, maternal dose, and rate of drug elimination by the newborn.
  • Pediatric: [US Boxed Warning]: Life-threatening respiratory depression and death have occurred in children who received codeine. Most of the reported cases occurred following tonsillectomy and/or adenoidectomy, and many of the children had evidence of being ultrarapid metabolizers of codeine due to a CYP2D6 polymorphism. Acetaminophen/codeine is contraindicated in pediatric patients <12 years of age and pediatric patients <18 years of age following tonsillectomy and/or adenoidectomy. Avoid the use of acetaminophen/codeine in pediatric patients 12 to 18 years of age who have other risk factors that may increase their sensitivity to the respiratory depressant effects of codeine. Risk factors include conditions associated with hypoventilation, such as postoperative status, obstructive sleep apnea, obesity, severe pulmonary disease, neuromuscular disease, and concomitant use of other medications that cause respiratory depression. Deaths have also occurred in breastfeeding infants after being exposed to high concentrations of morphine because the mothers were ultrarapid metabolizers.

Dosage form specific issues:

  • Benzyl alcohol and derivatives: Some dosage forms may contain sodium benzoate/benzoic acid; benzoic acid (benzoate) is a metabolite of benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol derivative with caution in neonates. See manufacturer's labeling.
  • Metabisulfite: Some products may contain metabisulfite, which may cause allergic reactions.
  • Oral solution and suspension: Risk of medication errors: [US Boxed Warning]: Ensure accuracy when prescribing, dispensing, and administering acetaminophen/codeine oral solution or suspension. Dosing errors due to confusion between mg and mL and other codeine-containing oral products of different concentrations can result in accidental overdose and death.
  • Propylene glycol: Some dosage forms may contain propylene glycol; large amounts are potentially toxic and have been associated hyperosmolality, lactic acidosis, seizures and respiratory depression; use caution (AAP ["Inactive" 1997]; Zar 2007).

Other warnings/precautions:

  • Abrupt discontinuation/withdrawal: Abrupt discontinuation in patients who are physically dependent on opioids has been associated with serious withdrawal symptoms, uncontrolled pain, attempts to find other opioids (including illicit), and suicide. Use a collaborative, patient-specific taper schedule that minimizes the risk of withdrawal, considering factors such as current opioid dose, duration of use, type of pain, and physical and psychological factors. Monitor pain control, withdrawal symptoms, mood changes, suicidal ideation, and for use of other substances; provide care as needed. Concurrent use of mixed agonist/antagonist (eg, pentazocine, nalbuphine, butorphanol) or partial agonist (eg, buprenorphine) analgesics may also precipitate withdrawal symptoms and/or reduced analgesic efficacy in patients following prolonged therapy with mu opioid agonists.
  • Abuse/misuse/diversion: [US Boxed Warning]: Use exposes patients and other users to the risks of opioid addiction, abuse, and misuse, which can lead to overdose and death. Assess each patient's risk prior to prescribing acetaminophen/codeine, and monitor all patients regularly for the development of these behaviors or conditions. Use with caution in patients with a history of drug abuse or acute alcoholism; potential for drug dependency exists. Other factors associated with increased risk for misuse include younger age, concomitant depression (major), and psychotropic medication use. Consider offering naloxone prescriptions in patients with factors associated with an increased risk for overdose, such as history of overdose or substance use disorder, higher opioid dosages (≥50 morphine milligram equivalents [MME]/day orally), and concomitant benzodiazepine use (Dowell [CDC 2016]). Abuse or misuse of ER tablets by crushing, chewing, snorting, or injecting the dissolved product will result in the uncontrolled delivery of the oxycodone and can result in overdose and death.
  • Accidental ingestion: [US Boxed Warning]: Accidental ingestion of acetaminophen/codeine, especially by children, can result in a fatal overdose of codeine.
  • Appropriate use: Chronic pain (outside of end-of-life or palliative care, active cancer treatment, sickle cell disease, or medication-assisted treatment for opioid use disorder) in outpatient setting in adults: Opioids should not be used as first-line therapy for chronic pain management (pain >3-month duration or beyond time of normal tissue healing) due to limited short-term benefits, undetermined long-term benefits, and association with serious risks (eg, overdose, MI, auto accidents, risk of developing opioid use disorder). Preferred management includes nonpharmacologic therapy and nonopioid therapy (eg, NSAIDs, acetaminophen, certain anticonvulsants and antidepressants). If opioid therapy is initiated, it should be combined with nonpharmacologic and nonopioid therapy, as appropriate. Prior to initiation, known risks of opioid therapy should be discussed and realistic treatment goals for pain/function should be established, including consideration for discontinuation if benefits do not outweigh risks. Therapy should be continued only if clinically meaningful improvement in pain/function outweighs risks. Therapy should be initiated at the lowest effective dosage using immediate-release opioids (instead of extended-release/long-acting opioids). Risk associated with use increases with higher opioid dosages. Risks and benefits should be re-evaluated when increasing dosage to ≥50 MME/day orally; dosages ≥90 MME/day orally should be avoided unless carefully justified (Dowell [CDC 2016]).
  • Dosage limit: Limit acetaminophen dose from all sources (prescription, OTC, combination products) to <4 g/day in adults. Do not use acetaminophen/codeine concomitantly with other acetaminophen-containing products.
  • Optimal regimen: An opioid-containing analgesic regimen should be tailored to each patient's needs and based upon the type of pain being treated (acute vs chronic), the route of administration, degree of tolerance for opioids (naive vs chronic user), age, weight, and medical condition. The optimal analgesic dose varies widely among patients; doses should be titrated to pain relief/prevention.
  • Risk Evaluation and Mitigation Strategy (REMS): [US Boxed Warning]: To ensure that the benefits of opioid analgesics outweigh the risks of addiction, abuse, and misuse, the FDA has required a REMS for these products. Under the requirements of the REMS, drug companies with approved opioid analgesic products must make REMS-compliant education programs available to health care providers. Health care providers are strongly encouraged to complete a REMS-compliant education program; counsel patients and/or their caregivers, with every prescription, on safe use, serious risks, storage, and disposal of these products; emphasize to patients and their caregivers the importance of reading the Medication Guide every time it is provided by their pharmacist; and consider other tools to improve patient, household, and community safety.
  • Surgery: Opioids decrease bowel motility; monitor for decreased bowel motility in postop patients receiving opioids. Use with caution in the perioperative setting; individualize treatment when transitioning from parenteral to oral analgesics.

Monitoring Parameters

Pain relief, respiratory and mental status, blood pressure, heart rate; bowel function; signs/symptoms of addiction, abuse, or misuse; signs or symptoms of hypogonadism or hypoadrenalism (Brennan 2013)

Alternate recommendations: Chronic pain (long-term therapy outside of end-of-life or palliative care, active cancer treatment, sickle cell disease, or medication-assisted treatment for opioid use disorder): Evaluate benefits/risks of opioid therapy within 1 to 4 weeks of treatment initiation and with dose increases. Re-evaluate benefits/risks every 3 months during therapy or more frequently in patients at increased risk of overdose or opioid use disorder. Urine drug testing is recommended prior to initiation and re-checking should be considered at least yearly (includes controlled prescription medications and illicit drugs of abuse). State prescription drug monitoring program (PDMP) data should be reviewed by clinicians prior to initiation and periodically during therapy (frequency ranging from every prescription to every 3 months) (Dowell [CDC 2016]).

Pregnancy

Pregnancy Considerations

[US Boxed Warning]: Prolonged use during pregnancy can result in neonatal opioid withdrawal syndrome, which may be life-threatening if not recognized and treated, and requires management according to protocols developed by neonatology experts. If opioid use is required for a prolonged period in a pregnant woman, advise the patient of the risk of neonatal opioid withdrawal syndrome and ensure that appropriate treatment will be available.

Refer to individual monographs for additional information.

Patient Education

What is this drug used for?

  • It is used to ease pain.

Frequently reported side effects of this drug

  • Abdominal pain
  • Sweating a lot
  • Nausea
  • Vomiting

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

  • Liver problems like dark urine, fatigue, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin.
  • Severe dizziness
  • Passing out
  • Chest pain
  • Confusion
  • Severe constipation
  • Severe loss of strength and energy
  • Unable to pass urine
  • Change in amount of urine passed
  • Chills
  • Sore throat
  • Mood changes
  • Severe headache
  • Difficulty breathing
  • Slow breathing
  • Shallow breathing
  • Fast heartbeat
  • Noisy breathing
  • Seizures
  • Bruising
  • Bleeding
  • Vision changes
  • Severe fatigue
  • Sexual dysfunction (males)
  • No menstrual periods
  • Decreased sex drive
  • Trouble getting pregnant
  • Adrenal gland problems like severe nausea, vomiting, severe dizziness, passing out, muscle weakness, severe fatigue, mood changes, lack of appetite, or weight loss
  • Serotonin syndrome like dizziness, severe headache, agitation, sensing things that seem real but are not, fast heartbeat, arrhythmia, flushing, tremors, sweating a lot, change in balance, severe nausea, or severe diarrhea
  • Stevens-Johnson syndrome/toxic epidermal necrolysis like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in mouth, throat, nose, or eyes
  • 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 February 7, 2020.