Colchicine and Ritonavir interaction
Colchicine 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 Colchicine label · effective 2026-03-18
Patients with renal or hepatic impairment should not be given colchicine capsules with drugs that inhibit both P-glycoprotein and CYP3A4 inhibitors [see Drug Interactions (7) ] .
• Drug interaction with dual P-gp and CYP3A4 inhibitors: Co-administration of colchicine with dual P-gp and CYP3A4 inhibitors has resulted in life-threatening interactions and death ( 5.3 , 7 ).
Therefore, concomitant use of colchicine capsules and inhibitors of CYP3A4 or P-glycoprotein should be avoided [see Drug Interactions (7) ] .
Fatal drug interactions have been reported when colchicine is administered with clarithromycin, a dual inhibitor of CYP3A4 and P-glycoprotein.
• Concomitant use of colchicine capsules and inhibitors of CYP3A4 or P-gp should be avoided if possible.
From the Ritonavir (Norvir) label · effective 2026-07-23
…Adrenoreceptor 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:…
Anti-gout: colchicine ↑ colchicine Contraindicated due to potential for serious and/or life-threatening reactions in patients with renal and/or hepatic impairment [see Contraindications ( 4 ) ] .
For patients with normal renal or hepatic function: Treatment of gout flares-co-administration of colchicine in patients on ritonavir: 0.6 mg (one tablet) for one dose, followed by 0.3 mg (half tablet) one hour later.
Prophylaxis of gout flares-co-administration of colchicine in patients on ritonavir: If the original colchicine regimen was 0.6 mg twice a day, the regimen should be adjusted to 0.3 mg once a day.If the original colchicine regimen was 0.6 mg once a day, the regimen should be adjusted to 0.3 mg once every other day.
Treatment of familial Mediterranean fever (FMF)-co-administration of colchicine in patients on ritonavir: Maximum daily dose of 0.6 mg (may be given as 0.3 mg twice a day).
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.