Quetiapine and Ritonavir interaction
Quetiapine and Ritonavir: 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 Ritonavir (Norvir) label · effective 2026-07-23
WARNING: DRUG-DRUG INTERACTIONS LEADING TO POTENTIALLY SERIOUS AND/OR LIFE THREATENING REACTIONS Co-administration of NORVIR with several classes of drugs including sedative hypnotics, antiarrhythmics, or ergot alkaloid preparations may result in potentially serious and/or life-threatening adverse events due to possible effects of NORVIR on the hepatic metabolism…
…POTENTIALLY SERIOUS AND/OR LIFE THREATENING REACTIONS See full prescribing information for complete boxed warning Co-administration of NORVIR with several classes of drugs including sedative hypnotics, antiarrhythmics, or ergot alkaloid preparations may result in potentially serious and/or life-threatening adverse events due to possible effects of NORVIR on the…
…Antagonist: alfuzosin ○ Antianginal: ranolazine ○ Antiarrhythmics: amiodarone, dronedarone, flecainide, propafenone, quinidine ○ Antifungal: voriconazole ○ Anti-gout: colchicine ○ Antipsychotics: lurasidone, pimozide ○ Ergot Derivatives: dihydroergotamine, ergotamine, methylergonovine ○ GI Motility Agent: cisapride ○ HMG-CoA Reductase Inhibitors: lovastatin,…
Antipsychotics: lurasidone pimozide ↑ lurasidone ↑ pimozide Contraindicated due to potential for serious and/or life-threatening reactions [see Contraindications ( 4 ) ] .
Sedative/Hypnotics: triazolam, orally administered midazolam ↑ triazolam ↑ midazolam Contraindicated due to potential for prolonged or increased sedation or respiratory depression [see Contraindications ( 4 ) ] .
From the Quetiapine (SEROQUEL XR) label · effective 2026-04-10
• Concomitant use of strong CYP3A4 inhibitors: Reduce quetiapine dose to one‑sixth when coadministered with strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir) ( 2.5 , 7.1 , 12.3 )
• Concomitant use of strong CYP3A4 inducers: Increase quetiapine dose up to 5 fold when used in combination with a chronic treatment (more than 7-14 days) of potent CYP3A4 inducers (e.g., phenytoin, rifampin, St.
• Discontinuation of strong CYP3A4 inducers: Reduce quetiapine dose by 5‑fold within 7-14 days of discontinuation of CYP3A4 inducers ( 2.6 , 7.1 , 12.3 )
Quetiapine exposure is increased by the prototype CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, indinavir, ritonavir, nefazodone, etc.) and decreased by the prototype of CYP3A4 inducers (e.g., phenytoin, carbamazepine, rifampin, avasimibe, St.
John’s wort etc.). Dose adjustment of quetiapine will be necessary if it is co-administered with potent CYP3A4 inducers or inhibitors.
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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.