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Acetaminophen, Caffeine, and Dihydrocodeine

Generic name: acetaminophen/caffeine/dihydrocodeine systemic

Brand names: Panlor DC, Panlor SS, Zerlor, Trezix, DHC Plus, Panlor, Dvorah

Boxed Warning

Addiction, abuse, and misuse:

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, and monitor all patients regularly for the development of these behaviors and 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. Monitor for respiratory depression, especially during initiation of therapy or following a dose increase.

Accidental ingestion:

Accidental ingestion, especially by children, can result in a fatal overdose of dihydrocodeine.

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 an ultra-rapid metabolizer of codeine due to cytochrome P450 (CYP-450) 2D6 polymorphism. Acetaminophen/caffeine/dihydrocodeine 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/caffeine/dihydrocodeine 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 opioids 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.

Interactions with drugs affecting cytochrome P450 isoenzymes

The effects of concomitant use or discontinuation of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complex. Use of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with acetaminophen/caffeine/dihydrocodeine requires careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine.

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 1 acetaminophen-containing product.

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/caffeine/dihydrocodeine 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

Capsule, Oral:

Trezix: Acetaminophen 320.5 mg, caffeine 30 mg, and dihydrocodeine bitartrate 16 mg

Trezix: Acetaminophen 356.4 mg, caffeine 30 mg, and dihydrocodeine bitartrate 16 mg [DSC]

Generic: Acetaminophen 320.5 mg, caffeine 30 mg, and dihydrocodeine bitartrate 16 mg

Tablet, Oral:

Panlor: Acetaminophen 325 mg, caffeine 30 mg, and dihydrocodeine bitartrate 16 mg [DSC]

Generic: Acetaminophen 325 mg, caffeine 30 mg, and dihydrocodeine bitartrate 16 mg [DSC]; Acetaminophen 712.8 mg, caffeine 60 mg, and dihydrocodeine bitartrate 32 mg [DSC]

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.

Caffeine: CNS stimulant; use with acetaminophen and dihydrocodeine increases the level of analgesia provided by each agent.

Dihydrocodeine: Binds to opiate receptors in the CNS, causing inhibition of ascending pain pathways, altering the perception of and response to pain; produces generalized CNS depression.

Use: Labeled Indications

Pain management: Management of pain severe enough to require an opioid analgesic 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 to provide sufficient management of pain.

Contraindications

Hypersensitivity (eg, anaphylaxis) to acetaminophen, caffeine, dihydrocodeine, 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 unmonitored settings or in the absence of resuscitative equipment; hypercapnia; GI obstruction, including paralytic ileus (known or suspected).

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

Pain management: Oral:

Capsule (acetaminophen 320.5 mg/caffeine 30 mg/dihydrocodeine bitartrate 16 mg): Two capsules every 4 hours as needed; adjust dose based on severity of pain (maximum dose: 10 capsules [acetaminophen 3,205 mg/caffeine 300 mg/dihydrocodeine 160 mg] per 24 hours)

Tablet (acetaminophen 325 mg/caffeine 30 mg/dihydrocodeine bitartrate 16 mg): Two tablets every 4 hours as needed; adjust dose based on severity of pain (maximum dose: 10 tablets [acetaminophen 3,250 mg/caffeine 300 mg/dihydrocodeine 160 mg] per 24 hours)

Tablet (acetaminophen 712.8 mg/caffeine 60 mg/dihydrocodeine bitartrate 32 mg): One tablet every 4 hours as needed; adjust dose based on severity of pain (maximum dose: 5 tablets [acetaminophen 3,564 mg/caffeine 300 mg/dihydrocodeine 160 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 alpha-2 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. Initiate therapy at low end of dosing range and use caution.

Storage

Store at 20°C to 25°C (68°F to 77°F). Protect from moisture.

Acetaminophen, Caffeine, and Dihydrocodeine Images

Drug Interactions

Acebrophylline: May enhance the stimulatory effect of CNS Stimulants. Avoid combination

Adenosine: Caffeine and Caffeine Containing Products may diminish the therapeutic effect of Adenosine. Management: Monitor for decreased effect of adenosine if patient is receiving caffeine. Discontinue caffeine in advance of scheduled diagnostic use of adenosine whenever possible. Consider therapy modification

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

Amifampridine: Agents With Seizure Threshold Lowering Potential may enhance the neuroexcitatory and/or seizure-potentiating effect of Amifampridine. Monitor therapy

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

AtoMOXetine: May enhance the hypertensive effect of Sympathomimetics. AtoMOXetine may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

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

Broccoli: May decrease the serum concentration of CYP1A2 Substrates (High risk with Inducers). 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

BuPROPion: May enhance the neuroexcitatory and/or seizure-potentiating effect of Agents With Seizure Threshold Lowering Potential. Monitor therapy

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 decrease the serum concentration of CYP1A2 Substrates (High risk with Inducers). 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

Cocaine (Topical): May enhance the hypertensive effect of Sympathomimetics. Management: Consider alternatives to use of this combination when possible. Monitor closely for substantially increased blood pressure or heart rate and for any evidence of myocardial ischemia with concurrent use. Consider therapy modification

CYP1A2 Inducers (Moderate): May decrease the serum concentration of Caffeine and Caffeine Containing Products. Monitor therapy

CYP1A2 Inhibitors (Moderate): May increase the serum concentration of Caffeine and Caffeine Containing Products. Monitor therapy

CYP1A2 Inhibitors (Strong): May increase the serum concentration of Caffeine and Caffeine Containing Products. Monitor therapy

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

Doxofylline: Caffeine and Caffeine Containing Products may enhance the adverse/toxic effect of Doxofylline. Avoid combination

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

Formoterol: Caffeine and Caffeine Containing Products may enhance the adverse/toxic effect of Formoterol. Caffeine and Caffeine Containing Products may enhance the hypokalemic effect of Formoterol. Monitor therapy

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

Guanethidine: May enhance the arrhythmogenic effect of Sympathomimetics. Guanethidine may enhance the hypertensive effect of Sympathomimetics. 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

Indacaterol: Caffeine and Caffeine Containing Products may enhance the adverse/toxic effect of Indacaterol. Caffeine and Caffeine Containing Products may enhance the hypokalemic effect of Indacaterol. Monitor therapy

Iohexol: Agents With Seizure Threshold Lowering Potential may enhance the adverse/toxic effect of Iohexol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iohexol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic anticonvulsants. Consider therapy modification

Iomeprol: Agents With Seizure Threshold Lowering Potential may enhance the adverse/toxic effect of Iomeprol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iomeprol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic anticonvulsants. Consider therapy modification

Iopamidol: Agents With Seizure Threshold Lowering Potential may enhance the adverse/toxic effect of Iopamidol. Specifically, the risk for seizures may be increased. Management: Discontinue agents that may lower the seizure threshold 48 hours prior to intrathecal use of iopamidol. Wait at least 24 hours after the procedure to resume such agents. In nonelective procedures, consider use of prophylactic anticonvulsants. Consider therapy modification

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

Linezolid: May enhance the hypertensive effect of Sympathomimetics. Management: Reduce initial doses of sympathomimetic agents, and closely monitor for enhanced pressor response, in patients receiving linezolid. Specific dose adjustment recommendations are not presently available. Consider therapy modification

Lithium: Caffeine and Caffeine Containing Products may decrease the serum concentration of Lithium. Monitor therapy

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

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: Dihydrocodeine may enhance the serotonergic effect of Monoamine Oxidase Inhibitors. This could result in serotonin syndrome. Monitor therapy

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

Norfloxacin: May increase the serum concentration of Caffeine and Caffeine Containing Products. Monitor therapy

Olodaterol: Caffeine and Caffeine Containing Products may enhance the adverse/toxic effect of Olodaterol. Caffeine and Caffeine Containing Products may enhance the hypokalemic effect of Olodaterol. 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

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

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

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

Pipemidic Acid: May increase the serum concentration of Caffeine and Caffeine Containing Products. 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

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

QuiNIDine: May diminish the analgesic effect of Dihydrocodeine. Specifically, quinidine may prevent the metabolic conversion of dihydrocodeine to its active metabolite Monitor therapy

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

Regadenoson: Caffeine and Caffeine Containing Products may diminish the vasodilatory effect of Regadenoson. Management: Avoiding using caffeine or other methylxanthine containing products (e.g., theophylline) for at least 12 hours prior to the administration of regadenoson. Consider therapy modification

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

Solriamfetol: Sympathomimetics may enhance the hypertensive effect of Solriamfetol. Monitor therapy

Solriamfetol: CNS Stimulants may enhance the hypertensive effect of Solriamfetol. Monitor therapy

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

Stiripentol: May increase the serum concentration of Caffeine and Caffeine Containing Products. Avoid combination

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

Sympathomimetics: May enhance the adverse/toxic effect of other Sympathomimetics. Monitor therapy

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

Tedizolid: May enhance the hypertensive effect of Sympathomimetics. Tedizolid may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

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

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

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

Tobacco (Smoked): May decrease the serum concentration of Caffeine and Caffeine Containing Products. Monitor therapy

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

Frequency not defined. Most common reactions with this combination include:

Central nervous system: Dizziness, drowsiness, sedation

Dermatologic: Dermatological reaction, pruritus

Gastrointestinal: Constipation, nausea, vomiting

Postmarketing and/or case reports: Hypogonadism (Brennan 2013; Debono 2011)

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 which require mental alertness (eg, operating machinery or driving).
  • Constipation: May cause constipation, which may 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 >1 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. Use with caution in patients with circulatory shock.
  • Phenanthrene hypersensitivity: Use opioids with caution in patients with hypersensitivity reactions to other phenanthrene-derivative opioid agonists (codeine, hydrocodone, hydromorphone, levorphanol, 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: Use with caution in patients with CNS depression or coma as these patients are susceptible to intracranial effects of CO2 retention.
  • Delirium tremens: Use with caution in patients with delirium tremens
  • Ethanol use: Use with caution in patients with alcoholic liver disease; consuming ≥3 alcoholic drinks/day may increase the risk of liver damage.
  • 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.
  • 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 and at a reduced dose 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 having a substantially decreased respiratory reserve, hypoxia, hypercarbia, or preexisting respiratory depression, particularly when initiating therapy 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 disorder; may cause or exacerbate preexisting 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 (CDC [Dowell2016]).
  • 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/caffeine/dihydrocodeine 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 cytochrome P450 (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/caffeine/dihydrocodeine 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 “ultra-rapid metabolizers”: Use caution in patients with two or more 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 patients, 0.5% to 1% of Hispanic patients, 1% to 10% of Caucasian patients, 3% of African-American patients, and 16% to 28% of North African, Ethiopian, and Arab patients.
  • 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 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. Prolonged use of opioids during pregnancy can cause neonatal 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 ultra-rapid metabolizers of codeine due to a CYP-450 2D6 polymorphism. Acetaminophen/caffeine/dihydrocodeine 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/caffeine/dihydrocodeine 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 nursing infants after being exposed to high concentrations of morphine because the mothers were ultra-rapid metabolizers. Use the lowest effective dose for the shortest period of time to reduce the risk of high concentrations of dihydromorphine.

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 and provide care as needed. Concurrent use of mixed agonist/antagonist analgesics (eg, pentazocine, nalbuphine, butorphanol) or partial agonist analgesics (eg, buprenorphine) 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/caffeine/dihydrocodeine, 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/day orally), and concomitant benzodiazepine use (Dowell [CDC 2016]).
  • Accidental ingestion: [US Boxed Warning]: Accidental ingestion, especially in children, can result in a fatal overdose of dihydrocodeine.
  • 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, nonsteroidal anti-inflammatory drugs, 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 morphine milligram equivalents (MME)/day orally; dosages ≥90 MME/day orally should be avoided unless carefully justified (Dowell [CDC 2016]).
  • Caffeine: May cause CNS and cardiovascular stimulation, as well as GI irritation in high doses.
  • Dosage limit: Limit acetaminophen dose from all sources (prescription and OTC) to <4 g/day in adults. Do not use acetaminophen/caffeine/dihydrocodeine concomitantly with other acetaminophen-containing products.
  • Optimal regimen: An opioid-containing analgesic regimen should be tailored to each patient's needs and based on the type of pain being treated (acute versus chronic), the route of administration, degree of tolerance for opioids (naive versus 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 decrease 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 misuse, abuse, and addiction; 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. Reevaluate 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.

Dihydrocodeine is a semisynthetic analogue of codeine; it has been shown to cause respiratory depression in the fetus when administered to women during labor (Leppert 2010; Myers 1958; Sliom 1970). Also refer to the Acetaminophen and Caffeine individual monographs for additional information.

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 nausea, vomiting, or sweating a lot. Have patient report immediately to prescriber signs of adrenal gland problems (severe nausea, vomiting, severe dizziness, passing out, muscle weakness, severe fatigue, mood changes, lack of appetite, or weight loss), signs of liver problems (dark urine, fatigue, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin), confusion, severe dizziness, passing out, change in balance, anxiety, severe loss of strength and energy, severe constipation, unable to pass urine, change in amount of urine passed, slow heartbeat, fast heartbeat, abnormal heartbeat, chills, sore throat, sensing things that seem real but are not, mood changes, noise or ringing in the ears, severe headache, severe fatigue, difficulty breathing, slow breathing, shallow breathing, noisy breathing, bruising, bleeding, vision changes, seizures, sexual dysfunction (males), no menstrual periods, decreased sex drive, trouble getting pregnant, signs of serotonin syndrome (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), or signs of Stevens-Johnson syndrome/toxic epidermal necrolysis (red, swollen, blistered, or peeling skin [with or without fever]; red or irritated eyes; or sores in mouth, throat, nose, or eyes) (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 15, 2020.