Colchicine and Fluconazole: 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
Fluconazole
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.
Fluconazole (Diflucan) can slow down how your body breaks down colchicine. When that happens, colchicine can build up to higher levels than intended, and that raises the risk of serious, even life-threatening side effects. Warning signs of too much colchicine include severe diarrhea, vomiting, stomach pain, muscle weakness, or unusual tingling.
The good news is that your care team can manage this. They may lower your colchicine dose, space out your doses, or watch you more closely while you take both. Please do not start, stop, or change either medicine on your own. Talk with your pharmacist or doctor so they can tailor your plan safely.
Mechanism: Fluconazole inhibits CYP3A4 (moderate inhibitor), reducing colchicine metabolism and increasing colchicine plasma exposure. Colchicine is not a prodrug, so inhibition raises active-drug levels and toxicity risk.
- Direction: increased colchicine exposure, risk of fatal toxicity.
- Evidence: theoretical; severity: major; onset unspecified.
- Management: avoid combination if possible. If required, reduce colchicine dose/frequency (e.g., gout flare: single 1.2 mg dose, no repeat sooner than 3 days; prophylaxis: 0.6 mg BID to 0.6 mg daily, or 0.6 mg daily to 0.3 mg daily; FMF max 1.2 mg/day).
- Avoid in renal or hepatic impairment. Monitor for colchicine toxicity and discontinue if suspected.
What happens
Increased colchicine exposure and an increased risk of fatal toxicity
Interaction Deep Dive
Colchicine should not be taken together with a moderate CYP3A4 inhibitor, because the combination can raise colchicine plasma levels and lead to fatal colchicine toxicity. When the two must be given together, the colchicine dose needs adjustment, achieved by lowering either the total daily amount or how often it is taken3. For situations requiring concurrent use, or use within a 14 day window, the colchicine regimen for a gout flare should be modified: rather than the usual 1.2 mg (2 tablets) followed one hour later by 0.6 mg (1 tablet), give a single 1.2 mg (2 tablet) dose, and do not repeat the dose until at least 3 days have passed. For gout flare prophylaxis, cut the colchicine dose from 0.6 mg twice daily down to 0.6 mg daily, or from 0.6 mg once daily down to 0.3 mg once daily. When patients with familial Mediterranean fever need colchicine alongside a moderate CYP3A4 inhibitor, the colchicine total should not exceed 1.2 mg per day (which may be administered as 0.6 mg twice daily). Watch for indications of colchicine toxicity and stop colchicine right away if it is suspected 2. In addition, combining colchicine with moderate CYP3A4 inhibitors should be avoided in patients who have renal or hepatic impairment 1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of colchicine
How to manage this interaction
Keep taking both exactly as prescribed unless your care team tells you otherwise. This combination is usually avoided when possible, but when it is needed it can be managed safely.
- Your colchicine dose may be lowered or given less often, and this will be individualized by your care team.
- Your team may monitor you more closely for signs of colchicine toxicity, such as severe diarrhea, vomiting, muscle weakness, or numbness and tingling.
- This combination is generally avoided if you have kidney or liver problems, so tell your team about those conditions.
Ask your pharmacist or prescriber before starting fluconazole, and report any new symptoms right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
Common questions
Can I take Colchicine and Fluconazole together?
Fluconazole can raise colchicine levels and increase the risk of serious toxicity, so this combination is best avoided; if both are needed, your care team will lower the colchicine dose and watch you closely. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Colchicine and Fluconazole interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
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 Fluconazole interaction managed?
Keep taking both exactly as prescribed unless your care team tells you otherwise. This combination is usually avoided when possible, but when it is needed it can be managed safely. Your colchicine dose may be lowered or given less often, and this will be individualized by your care team. Your team may monitor you more closely for signs of colchicine toxicity, such as severe diarrhea, vomiting, mus… 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.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Colchicine or Fluconazole 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 Fluconazole
Keep reading about Colchicine
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