Darunavir and Promethazine and codeine interaction
Darunavir and Promethazine and codeine: 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 Darunavir (PREZISTA) label · effective 2025-08-29
…elbasvir/grazoprevir Lipid modifying agents: lomitapide, lovastatin, simvastatin Opioid Antagonist: naloxegol PDE-5 inhibitor: sildenafil when used for treatment of pulmonary arterial hypertension Sedatives/hypnotics: orally administered midazolam, triazolam Co-administration of PREZISTA/ritonavir is contraindicated with drugs that are highly dependent on CYP3A for clearance…
Opioid Antagonist naloxegol ↑ naloxegol Co-administration of PREZISTA/ritonavir and naloxegol is contraindicated due to potential for precipitating opioid withdrawal symptoms.
Sedatives/hypnotics: orally administered midazolam, triazolam ↑ midazolam ↑ triazolam Co-administration is contraindicated due to potential for serious and/or life-threatening reactions such as prolonged or increased sedation or respiratory depression.
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 dose decrease may be needed for tramadol…
…administered midazolam with PREZISTA may cause large increases in the concentrations of these benzodiazepines. metabolized by CYP3A e.g. buspirone, diazepam, estazolam, zolpidem ↑ sedatives/hypnotics Titration is recommended when co-administering PREZISTA/ritonavir with sedatives/hypnotics metabolized by CYP3A and a lower dose of the sedatives/hypnotics should…
From the Promethazine and codeine (Promethazine Hydrochloride and Codeine Phosphate) label · effective 2025-12-18
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, requiring careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine.
Avoid the use of Promethazine HCl and Codeine Phosphate Oral Solution in patients who are taking a CYP3A4 inhibitor, CYP3A4 inducer, or 2D6 inhibitor [ see Warnings and Precautions (5.9) , Drug Interactions (7.1 , 7.2 , 7.3 ) ].
The effects of concomitant use or discontinuation of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complex, requiring careful consideration of the effects on the parent drug, codeine, and the active metabolite, morphine.
Avoid the use of Promethazine HCl and Codeine Phosphate Oral Solution in patients who are taking a CYP3A4 inhibitor or CYP3A4 inducer.
Avoid the use of Promethazine HCl and Codeine Phosphate Oral Solution in patients who are taking a CYP2D6 inhibitor.
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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.