Colchicine and Darunavir: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Darunavir
No brand names on recordColchicine
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
Darunavir is almost always taken with a booster called ritonavir, and together they strongly block a liver enzyme (CYP3A4) that normally breaks down colchicine. When that enzyme is blocked, colchicine can build up in your body to dangerous levels. Colchicine already has a narrow safety margin, and too much of it can cause serious, even life-threatening problems like severe diarrhea, muscle weakness, and damage to blood cells.
The good news is that your care team knows how to handle this. In some situations they avoid combining these drugs, and in others they carefully lower your colchicine dose and watch you closely. Please don't stop or change either medicine on your own, just talk with your pharmacist or doctor about taking them together.
Mechanism: Ritonavir-boosted darunavir is a strong CYP3A4 (and P-gp) inhibitor. Colchicine is a CYP3A4/P-gp substrate, so exposure (AUC/Cmax) rises, increasing risk of life-threatening colchicine toxicity (myelosuppression, neuromyopathy, multi-organ failure). Neither drug is a prodrug; this is a straightforward increase in colchicine effect.
- Severity: Contraindicated in renal or hepatic impairment.
- Evidence: Theoretical for this pair; extrapolated from fatal clarithromycin cases.
- Management (normal renal/hepatic function): Reduce colchicine. Gout flare: 0.6 mg x1, then 0.3 mg 1 hr later, no repeat course sooner than 3 days. Prophylaxis: 0.6 mg BID to 0.3 mg daily; 0.6 mg daily to 0.3 mg QOD. FMF: max 0.6 mg/day. Applies within 14 days of the inhibitor.
What happens
Increased colchicine exposure and an increased risk of colchicine toxicity
Interaction Deep Dive
Giving colchicine alongside a potent CYP3A4 inhibitor is contraindicated, since fatal and life-threatening colchicine toxicity has been documented in such patients even when colchicine was used at therapeutic doses1. Colchicine serves as a substrate for both CYP3A4 and P-glycoprotein (P-gp). When colchicine was combined with clarithromycin, a strong inhibitor of both CYP3A4 and P-gp, colchicine exposure rose substantially and fatal toxicity followed. Toxic effects have likewise been seen when colchicine was paired with a CYP3A4 inhibitor and when it was paired with a P-gp inhibitor3. In patients who have renal or hepatic impairment, the simultaneous use of colchicine with a potent CYP3A4 inhibitor (which includes every protease inhibitor apart from fosamprenavir) is contraindicated. For patients whose renal and hepatic function is normal, the colchicine dose must be modified when ritonavir-boosted darunavir is used at the same time or has been used within the previous 14 days. In treating a gout flare, cut the colchicine dose to a single 0.6 mg tablet, then 0.3 mg (half a tablet) one hour afterward, and do not repeat the dose sooner than 3 days. For gout flare prophylaxis, lower the dose from an initial 0.6 mg twice daily to 0.3 mg once daily, or from 0.6 mg once daily to 0.3 mg once every other day. In familial Mediterranean fever, the daily dose should not surpass 0.6 mg (which may be administered as 0.3 mg twice daily)2.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated colchicine metabolism by ritonavir-boosted darunavir
How to manage this interaction
This combination is manageable, but it needs your care team's oversight. Here is what they typically do:
- If you have kidney or liver problems, they usually avoid using these two together.
- If your kidney and liver function is normal, they lower your colchicine dose and may watch you more closely. Dosing is individualized based on why you take colchicine (gout flare, gout prevention, or familial Mediterranean fever).
- These precautions also apply if you took ritonavir-boosted darunavir within the last 14 days.
What you should do: Keep taking both exactly as prescribed, and don't adjust doses yourself. Tell your pharmacist and prescriber that you take both so they can set the right colchicine dose. Report severe diarrhea, muscle weakness, numbness, or unusual bruising right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) While the interaction between colchicine and ritonavir-boosted darunavir has not been investigated, an interaction between colchicine and clarithromycin, a potent CYP3A4 inhibitor, led to fatal colchicine toxicity. Following a single 0.6 mg colchicine dose given to patients (n=23) receiving clarithromycin 250 mg twice daily for 7 days, colchicine Cmax and AUC rose by 227.2% and 281.5%, respectively 2.
Common questions
Can I take Colchicine and Darunavir together?
Boosted darunavir can raise colchicine to toxic levels, so this pair is avoided in people with kidney or liver problems and requires a lowered, individualized colchicine dose in everyone else. Never combine or adjust these yourself without your pharmacist or doctor. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Colchicine and Darunavir interaction?
It is rated contraindicated. These should generally not be used together.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Colchicine and Darunavir interaction managed?
This combination is manageable, but it needs your care team's oversight. Here is what they typically do: If you have kidney or liver problems, they usually avoid using these two together. If your kidney and liver function is normal, they lower your colchicine dose and may watch you more closely. Dosing is individualized based on why you take colchicine (gout flare, gout prevention, or familial Med… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Colchicine or Darunavir need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (3)
- Product Information: LODOCO(R) oral tablets, colchicine oral tablets. AGEPHA Pharma USA, LLC (per FDA), Parsippany, NJ, 2023. DailyMed
- Product Information: COLCRYS oral tablets, colchicine oral tablets. Takeda Pharmaceuticals America Inc (per FDA), Deerfield, IL, 2020. DailyMed
- Product Information: GLOPERBA(R) oral solution, colchicine oral solution. Romeg Therapeutics LLC (per FDA), Woburn, MA, 2019. DailyMed
Keep reading about Darunavir
Keep reading about Colchicine
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