Flibanserin and Colchicine: 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
Flibanserin
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.
Flibanserin (Addyi) can slow down a natural 'pump' in your body called P-gp that normally helps clear colchicine out. When that pump is blocked, colchicine can build up to higher levels than expected. Because colchicine can be very toxic when it climbs too high (causing serious muscle, blood, and organ problems), this combination is considered one to avoid.
The good news is your care team can spot this ahead of time. Please don't stop either medicine on your own. Just let your pharmacist or doctor know you take both, and they can decide the safest plan for you.
Effect: Flibanserin (a P-gp inhibitor) may reduce P-gp-mediated efflux of colchicine, increasing colchicine exposure and risk of toxicity.
- Mechanism: Colchicine is a P-gp and CYP3A4 substrate; inhibition of intestinal/renal P-gp raises colchicine AUC.
- Direction: Increased colchicine effect/toxicity (neither drug is a prodrug).
- Severity/onset: Contraindicated; onset unspecified. Evidence is theoretical, extrapolated from documented P-gp inhibitor toxicity.
- Management: Contraindicated in renal or hepatic impairment. If coadministration is unavoidable in normal organ function, reduce colchicine daily dose or dosing frequency and monitor closely for toxicity (GI symptoms, myelosuppression, myopathy).
What happens
Increased colchicine exposure and an increased risk of colchicine toxicity
Interaction Deep Dive
Colchicine acts as a substrate for both CYP3A4 and P-gp. Cases of toxicity have been documented when it was given together with clarithromycin, an agent that inhibits both CYP3A4 and P-gp. Toxic effects have likewise arisen when colchicine was combined with a CYP3A4 inhibitor and when it was combined with a P-gp inhibitor3. Because life-threatening and fatal colchicine toxicity has been reported in patients taking therapeutic doses, the simultaneous use of colchicine with P-gp inhibitors is contraindicated 1. This combination is also contraindicated in individuals with renal or hepatic impairment, since life-threatening and fatal drug interactions have been observed. For patients whose renal and hepatic function is normal 2, when colchicine must be given alongside a P-gp inhibitor, modify the colchicine dose by lowering either the daily amount or the frequency of dosing. Watch carefully for signs of colchicine toxicity 3.
Why it happens (mechanism)
Inhibition of P-gp-mediated colchicine efflux transport
How to manage this interaction
Because colchicine can reach dangerous levels when combined with a P-gp inhibitor like flibanserin, this pairing is flagged as one to avoid, and it is especially unsafe if you have kidney or liver problems.
- Keep taking both exactly as prescribed until you speak with your care team; do not adjust anything yourself.
- Tell your pharmacist or prescriber that you take both drugs so they can choose the safest option.
- If both are truly needed and your kidneys and liver are healthy, your colchicine dose may be reduced or given less often, and your team may monitor you more closely for toxicity.
- Report muscle weakness, numbness, severe diarrhea, vomiting, or unusual fatigue right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Flibanserin and Colchicine together?
Flibanserin can raise colchicine levels and cause serious toxicity, so this combination is generally contraindicated. Let your pharmacist or doctor know you take both so they can adjust or change your therapy. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Flibanserin and Colchicine 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 Flibanserin and Colchicine interaction managed?
Because colchicine can reach dangerous levels when combined with a P-gp inhibitor like flibanserin, this pairing is flagged as one to avoid, and it is especially unsafe if you have kidney or liver problems. Keep taking both exactly as prescribed until you speak with your care team; do not adjust anything yourself. Tell your pharmacist or prescriber that you take both drugs so they can choose the s… 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 Flibanserin or Colchicine 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 Flibanserin
Keep reading about Colchicine
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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