Colchicine and Posaconazole: 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
Posaconazole
Colchicine
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.
These two medicines can be a dangerous mix. Posaconazole (Noxafil) is an antifungal that slows down a liver enzyme called CYP3A4. That same enzyme is what your body uses to break down colchicine. So when you take them together, colchicine can build up to very high levels in your body.
This matters a lot because too much colchicine can cause severe, even life-threatening poisoning. That is why doctors treat this combination very carefully, and in some people it should be avoided completely. Please do not stop or change either medicine on your own. Talk with your pharmacist or doctor first. They can adjust your colchicine dose safely or choose a different plan, and they can watch you closely for any problems.
Mechanism: Posaconazole is a strong CYP3A4 inhibitor; colchicine is a CYP3A4 (and P-gp) substrate. Inhibition reduces colchicine metabolism, increasing exposure (AUC/Cmax) and the risk of fatal toxicity. Colchicine is not a prodrug, so effect is potentiated.
Severity: Contraindicated. Evidence: probable.
- Absolute contraindication in renal or hepatic impairment.
- In normal renal/hepatic function, dose reduction is required if posaconazole given within 14 days.
- Gout flare: 0.6 mg once, then 0.3 mg 1 h later; no repeat sooner than 3 days.
- Gout prophylaxis: halve dose (e.g., 0.6 mg BID to 0.3 mg daily); if unavoidable, limit to 0.24 mg.
- FMF: max 0.6 mg/day.
Monitor closely for GI, myelosuppression, and neuromuscular toxicity.
What happens
Increased colchicine exposure and an increased risk of fatal toxicity
Interaction Deep Dive
Because life-threatening and fatal colchicine toxicity has been documented in patients taking therapeutic doses of colchicine together with strong CYP3A4 inhibitors like posaconazole, this combination is contraindicated1. Likewise, the pairing of colchicine with strong CYP3A4 inhibitors such as posaconazole is contraindicated in individuals who have renal or hepatic impairment, given the potential for serious or fatal toxicities. In patients whose renal and hepatic function is normal and who are taking a strong CYP3A4 inhibitor at the same time or have taken one within the previous 14 days, the colchicine dose must be adjusted. When treating a gout flare, lower the colchicine dose to a single 0.6 mg tablet followed by 0.3 mg one hour afterward, and do not repeat the dose sooner than 3 days. For gout flare prophylaxis, reduce colchicine from an initial dose of 0.6 mg twice daily to 0.3 mg once daily, or from an initial dose of 0.6 mg once daily to 0.3 mg once every other day. When treating familial Mediterranean fever, the daily colchicine dose should not exceed 0.6 mg (which may be administered as 0.3 mg twice daily)2. Concurrent use of colchicine with posaconazole should be avoided; however, if colchicine and posaconazole must be given together while colchicine is being used for gout prophylaxis, restrict the colchicine dose to 0.24 mg orally. Monitor closely for signs of colchicine toxicity3.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated colchicine metabolism by posaconazole
How to manage this interaction
This combination needs your care team's guidance. Keep taking both exactly as prescribed unless your prescriber or pharmacist tells you otherwise. Do not adjust doses yourself.
- Your team may avoid this combination altogether, especially if you have kidney or liver problems, where it should not be used.
- If both are needed and your kidney and liver function are normal, your colchicine dose will be lowered and individualized by your care team.
- They may monitor you more closely for signs of colchicine toxicity, such as nausea, vomiting, diarrhea, muscle weakness, or unusual tiredness.
Call your pharmacist or doctor if you notice any of these symptoms.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) Giving colchicine together with posaconazole 300 mg once daily (regarded as a strong CYP3A4 inhibitor) raised the AUC of colchicine by roughly 3-fold 3.
Common questions
Can I take Colchicine and Posaconazole together?
Posaconazole can raise colchicine to toxic, potentially fatal levels, so this pairing is contraindicated and must be avoided or carefully dose-adjusted. Never combine them without your doctor or pharmacist adjusting the colchicine dose first. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Colchicine and Posaconazole 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 Posaconazole interaction managed?
This combination needs your care team's guidance. Keep taking both exactly as prescribed unless your prescriber or pharmacist tells you otherwise. Do not adjust doses yourself. Your team may avoid this combination altogether, especially if you have kidney or liver problems, where it should not be used. If both are needed and your kidney and liver function are normal, your colchicine dose will be l… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Colchicine or Posaconazole 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 Posaconazole
Keep reading about Colchicine
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