Colchicine and Itraconazole: 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
Itraconazole
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.
Itraconazole (Sporanox) and colchicine (Colcrys) can be a dangerous combination. Your body normally clears colchicine using two systems: an enzyme called CYP3A4 and a pump called P-gp. Itraconazole blocks both of them. That means colchicine can build up to high levels in your body, and too much colchicine can cause serious, even life-threatening problems like severe stomach upset, muscle damage, and blood cell issues.
This is a serious pairing, and in people with kidney or liver problems it should not be used together at all. Please don't stop or change either medicine on your own. Talk with your pharmacist or doctor. They can safely adjust your colchicine dose or choose a different plan for you.
Effect: Increased colchicine exposure and risk of colchicine toxicity.
Mechanism: Colchicine is a substrate of both CYP3A4 and P-gp. Itraconazole is a dual strong CYP3A4 and P-gp inhibitor, reducing colchicine metabolism and efflux, raising plasma concentrations (neither drug is activated by this pathway; the parent effect is amplified).
- Severity: Contraindicated; evidence: theoretical, but fatal toxicity documented with analogous dual inhibitors (e.g., clarithromycin).
- Contraindicated in renal or hepatic impairment.
- If used with normal organ function: reduce colchicine dose. Gout flare: 0.6 mg x1 then 0.3 mg 1 h later, no repeat course sooner than 3 days. Prophylaxis: 0.3 mg daily or every other day. FMF: max 0.6 mg/day.
- Avoid colchicine for up to 2 weeks after itraconazole discontinuation. Monitor for GI, myotoxic, and hematologic effects.
What happens
Increased colchicine exposure and an increased risk of colchicine toxicity
Interaction Deep Dive
Both CYP3A4 and P-gp metabolize colchicine, making it a substrate of each. Giving colchicine together with agents that strongly inhibit both CYP3A4 and P-glycoprotein (P-gp) is contraindicated1. Coadministration of colchicine with clarithromycin, an inhibitor of both CYP3A4 and P-gp, has produced fatal drug interactions and serious toxicities. Similar toxicities have been documented when colchicine is combined with CYP3A4 inhibitors and when it is combined with P-gp inhibitors. In patients who have renal or hepatic impairment, combining colchicine with dual CYP3A4/P-gp inhibitors like itraconazole is contraindicated, and this combination should be avoided in every patient whenever feasible3. When patients with normal renal and hepatic function must take itraconazole concurrently, or have taken it within the previous 14 days, the colchicine dose must be modified. For treating a gout flare, lower the colchicine dose to a single 0.6 mg tablet, then 0.3 mg one hour afterward, and do not repeat the dose sooner than 3 days. For gout flare prophylaxis, cut the dose from 0.6 mg twice daily down to 0.3 mg once daily or once every other day. When treating familial Mediterranean fever, colchicine should not exceed a maximum of 0.6 mg/day2. Colchicine should not be given for up to 2 weeks following discontinuation of itraconazole. Watch for indications of amplified or prolonged effects5.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of colchicine; inhibition of P-gp-mediated efflux transport of colchicine
How to manage this interaction
This combination is generally avoided, and off-limits if you have kidney or liver problems. Keep taking both medicines exactly as prescribed until you speak with your care team, but raise this pairing with them promptly.
Here is what your team typically does:
- Lower your colchicine dose and individualize it for you if the two must be used together (they have specific reduced-dose schedules for gout treatment, gout prevention, and familial Mediterranean fever).
- Keep colchicine paused for up to 2 weeks after itraconazole is stopped, since the effect lingers.
- Watch you more closely for signs of colchicine toxicity like severe diarrhea, nausea, muscle pain or weakness, numbness, or unusual tiredness.
Call your doctor or pharmacist right away if any of those symptoms appear.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In a study involving 23 patients, taking a 0.6 mg dose of colchicine together with clarithromycin 250 mg twice daily over 7 days led to increases of 227.2% in colchicine Cmax and 281.5% in colchicine AUC relative to baseline 2.
Common questions
Can I take Colchicine and Itraconazole together?
Itraconazole can push colchicine to toxic levels, so the combination is contraindicated (especially with kidney or liver problems); do not change either drug yourself, and ask your pharmacist or doctor to adjust the colchicine dose or find an alternative. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Colchicine and Itraconazole 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 Itraconazole interaction managed?
This combination is generally avoided, and off-limits if you have kidney or liver problems. Keep taking both medicines exactly as prescribed until you speak with your care team, but raise this pairing with them promptly. Here is what your team typically does: Lower your colchicine dose and individualize it for you if the two must be used together (they have specific reduced-dose schedules for gout… 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 Itraconazole 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 (5)
- 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
- Product Information: SPORANOX(R) oral capsules, itraconazole oral capsules. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
- Product Information: SPORANOX(R) oral solution, itraconazole oral solution. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
Keep reading about Itraconazole
Keep reading about Colchicine
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