Colchicine and Isavuconazole: 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
Colchicine
Isavuconazole
No brand names on record
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. Colchicine treats gout and some other conditions, and your body clears it out using a specific enzyme (CYP3A4) and a transporter pump (P-gp). Isavuconazole, an antifungal, slows down both of those clean-up systems. That means colchicine can build up to high levels in your body.
Too much colchicine can cause serious harm, including severe stomach upset, muscle damage, blood problems, and in the worst cases it can be life-threatening. This is especially risky if your kidneys or liver don't work well. Please don't stop either drug on your own, but reach out to your pharmacist or doctor promptly so they can review your medicines and keep you safe.
Effect: Isavuconazole inhibits both CYP3A4-mediated metabolism and P-gp-mediated efflux of colchicine, increasing colchicine exposure (AUC/Cmax) and the risk of serious, potentially fatal toxicity.
- Direction: Increased colchicine effect/toxicity (neither drug is a prodrug).
- Severity/evidence: Contraindicated; substantiation probable.
- Management: Coadministration is contraindicated in patients with renal or hepatic impairment. If use is otherwise necessary, reduce the colchicine daily dose by 50% to 75% or reduce dosing frequency per labeling, and monitor for colchicine toxicity (GI symptoms, myotoxicity, myelosuppression).
What happens
Increased colchicine exposure and an increased risk of fatal toxicity
Interaction Deep Dive
Colchicine is contraindicated when taken together with P-gp inhibitors1. Using colchicine at the same time as agents that inhibit both CYP3A4 and P-gp carries the risk of serious, potentially fatal toxicity. When colchicine must be given alongside a P-gp inhibitor, its dosing should be modified, either by lowering the daily dose by 50% to 75% 3 or by spacing out how often it is taken. In patients who have renal or hepatic impairment, the combined use of colchicine with P-gp and CYP3A4 inhibitors is contraindicated 3. In such patients with renal and hepatic impairment, pairing these inhibitors with colchicine has led to colchicine toxicity that was life-threatening or fatal 2.
Why it happens (mechanism)
Inhibition of P-gp-mediated efflux transport of colchicine; inhibition of CYP3A4-mediated metabolism of colchicine
How to manage this interaction
Take this combination seriously and loop in your care team. Because isavuconazole blocks the pathways that clear colchicine, your prescriber may:
- Avoid the combination altogether, particularly if you have kidney or liver problems, where it is contraindicated.
- If both are truly needed, reduce your colchicine dose (often by 50% to 75%) or space out how often you take it. Any dose change must be individualized by your care team.
- Monitor you more closely for signs of colchicine toxicity.
Keep taking both exactly as prescribed for now, and watch for severe diarrhea, vomiting, muscle weakness or pain, numbness, or unusual bruising. Report these and confirm your plan with your pharmacist or doctor.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Colchicine and Isavuconazole together?
Isavuconazole can raise colchicine to toxic levels, so this pairing is contraindicated, especially with kidney or liver problems. Do not change anything yourself; contact your pharmacist or doctor to review your dose and safer options. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Colchicine and Isavuconazole 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 Isavuconazole interaction managed?
Take this combination seriously and loop in your care team. Because isavuconazole blocks the pathways that clear colchicine, your prescriber may: Avoid the combination altogether, particularly if you have kidney or liver problems, where it is contraindicated. If both are truly needed, reduce your colchicine dose (often by 50% to 75%) or space out how often you take it. Any dose change must be indi… 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 Isavuconazole 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: MITIGARE(R) oral capsules, colchicine oral capsules. Hikma Specialty USA Inc (per FDA), Columbus, OH, 2024. DailyMed
- Hansten PD, Tan MS, Horn JR, et al: Colchicine drug interaction errors and misunderstandings: recommendations for improved evidence-based management. Drug Saf 2023; 46(3):223-242. PubMed
Keep reading about Colchicine
Keep reading about Isavuconazole
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