Darunavir and cobicistat and Tetrabenazine interaction
Darunavir and cobicistat and Tetrabenazine: 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 and cobicistat (PREZCOBIX) label · effective 2026-02-01
…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 PREZCOBIX or PREZCOBIX PED is contraindicated in patients receiving certain co-administered drugs for which altered plasma…
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.
…midazolam with PREZCOBIX or PREZCOBIX PED may cause large increases in the concentrations of these benzodiazepines. metabolized by CYP3A: e.g. buspirone, diazepam, estazolam, zolpidem ↑ sedatives/hypnotics With concomitant use, titration is recommended with sedatives/hypnotics metabolized by CYP3A and a lower dose of the sedatives/hypnotics should be considered with…
From the Tetrabenazine label · effective 2019-11-29
• Do not exceed 50 mg/day and the maximum single dose should not exceed 25 mg if administered in conjunction with a strong CYP2D6 inhibitor (e.g., fluoxetine, paroxetine).
Strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine, quinidine) markedly increase exposure to these metabolites.
A reduction in tetrabenazine tablets dose may be necessary when adding a strong CYP2D6 inhibitor (e.g., fluoxetine, paroxetine, quinidine) in patients maintained on a stable dose of tetrabenazine tablets.
The daily dose of tetrabenazine should not exceed 50 mg/day and the maximum single dose of tetrabenazine tablets should not exceed 25 mg in patients taking strong CYP2D6 inhibitors [see Dosage and Administration (2.3) , Warnings and Precautions (5.3) , Use in Specific Populations ( 8.7 ), Clinical Pharmacology (12.3) ].
Strong CYP2D6 Inhibitors In vitro studies indicate that α-HTBZ and β-HTBZ are substrates for CYP2D6.
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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.