Acetaminophen and codeine and Lenacapavir interaction
Acetaminophen and codeine and Lenacapavir: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Acetaminophen and codeine (ACETAMINOPHEN AND CODEINE PHOSPHATE) label · effective 2026-01-22
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 and codeine phosphate tablets requires careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine ( see WARNINGS and PRECAUTIONS, Drug Interactions ).
Cytochrome P450 3A4 Interaction The concomitant use of acetaminophen and codeine phosphate tablets with all cytochrome P450 3A4 inhibitors, such as macrolide antibiotics (e.g., erythromycin), azole-antifungal agents (e.g., ketoconazole), and protease inhibitors (e.g., ritonavir) or discontinuation of a cytochrome P450 3A4 inducer such as rifampin, carbamazepine,…
The concomitant use of acetaminophen and codeine phosphate tablets with all cytochrome P450 3A4 inducers or discontinuation of a cytochrome P450 3A4 inhibitor may result in lower codeine levels, greater norcodeine levels, and less metabolism via 2D6 with resultant lower morphine levels.
Evaluate patients receiving acetaminophen and codeine phosphate tablets and any CYP3A4 inhibitor or inducer for signs and symptoms that may reflect opioid toxicity and opioid withdrawal when acetaminophen and codeine phosphate tablets are used in conjunction with inhibitors and inducers of CYP3A4 ( see PRECAUTIONS, Drug Interactions ).
From the Lenacapavir (Sunlenca) label · effective 2026-08-27
Opioid Antagonist: naloxegol ↑ naloxegol Avoid use with SUNLENCA; if unavoidable, decrease the dosage of naloxegol and monitor for adverse reactions.
Narcotic analgesics metabolized by CYP3A: e.g., fentanyl, oxycodone ↑ fentanyl ↑ oxycodone Careful monitoring of therapeutic effects and adverse reactions associated with CYP3A-metabolized narcotic analgesics (including potentially fatal respiratory depression) is recommended with co-administration. tramadol ↑ tramadol A decrease in dose may be needed for tramadol…
Narcotic analgesic for treatment of opioid dependence: buprenorphine, methadone buprenorphine: effects unknown methadone: effects unknown Initiation of buprenorphine or methadone in patients taking SUNLENCA: Carefully titrate the dose of buprenorphine or methadone to the desired effect; use the lowest feasible initial or maintenance dose.
Sedatives/Hypnotics: midazolam (oral) triazolam ↑ midazolam (oral) ↑ triazolam Use with caution when midazolam or triazolam is concomitantly administered with SUNLENCA 7.4 Drugs without Clinically Significant Interactions with SUNLENCA Based on drug interaction studies conducted with SUNLENCA, no clinically significant drug interactions have been observed with:…
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.