Colchicine and Gepotidacin: 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
Gepotidacin
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.
Here's what's going on. Your body uses an enzyme called CYP3A4 to break down colchicine. Gepotidacin (Blujepa) is an antibiotic that can slow this enzyme down. When that happens, colchicine can build up in your body more than it should.
Colchicine has a narrow safety window, meaning even a small increase can matter. Higher levels raise the chance of side effects like nausea, diarrhea, stomach pain, or muscle problems. The good news is this is very manageable. Your pharmacist or doctor can look at both medicines together and decide the safest plan, so please check with them before taking these two at the same time.
Mechanism: Gepotidacin inhibits CYP3A4, reducing metabolism of CYP3A4 substrates. Colchicine is a CYP3A4 (and P-gp) substrate with a narrow therapeutic index, so co-administration is expected to increase colchicine exposure and toxicity risk.
- Direction: increased colchicine AUC/Cmax (elevated effect and toxicity).
- Magnitude: midazolam probe showed ~1.9-fold AUC increase (supratherapeutic gepotidacin dosing).
- Evidence: probable; onset: unspecified.
- Management: avoid concomitant use per labeling. If unavoidable, individualize colchicine dosing and monitor closely for GI, neuromuscular, and hematologic toxicity, with heightened caution in renal/hepatic impairment.
What happens
Increased CYP3A4 substrate with NTI exposure
Interaction Deep Dive
Concurrent use of gepotidacin with CYP3A4 substrates that have a narrow therapeutic index should be avoided, since it can raise the exposure of the NTI CYP3A4 substrate. When midazolam (a CYP3A4 substrate) was given as a single 2 mg dose together with gepotidacin (two 3,000 mg doses administered 12 hours apart, which is not an approved gepotidacin dosage), the AUC(0 to inf) of midazolam rose by 1.9-fold1.
Why it happens (mechanism)
Inhibition of CYP3A4-substrate metabolism by gepotidacin
How to manage this interaction
What your care team may do:
- Often they will avoid using these two together, since the label recommends avoiding gepotidacin with narrow-therapeutic-index CYP3A4 substrates like colchicine.
- If both are truly needed, your colchicine dose may need to be adjusted and individualized by your care team, and they may monitor you more closely.
What you should do: Keep taking both exactly as prescribed and do not stop or change anything on your own. Tell your pharmacist or prescriber you are on colchicine before starting gepotidacin, and report any nausea, diarrhea, severe stomach pain, muscle weakness, or unusual fatigue promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) When midazolam (a CYP3A4 substrate) was given as a single 2 mg dose together with gepotidacin (two 3,000 mg doses administered 12 hours apart, which is not an approved dosage of gepotidacin), the midazolam AUC(0 to inf) increased 1.9-fold 1.
Common questions
Can I take Colchicine and Gepotidacin together?
Gepotidacin can raise colchicine levels and its side effect risk, so these are generally avoided together. Check with your pharmacist or doctor before combining them. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Colchicine and Gepotidacin 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 Gepotidacin interaction managed?
What your care team may do: Often they will avoid using these two together, since the label recommends avoiding gepotidacin with narrow-therapeutic-index CYP3A4 substrates like colchicine. If both are truly needed, your colchicine dose may need to be adjusted and individualized by your care team, and they may monitor you more closely. What you should do: Keep taking both exactly as prescribed and… 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 Gepotidacin 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 (1)
- Product Information: BLUJEPA oral tablets, gepotidacin oral tablets. GlaxoSmithKline (per FDA), Durham, NC, 2025. DailyMed
Keep reading about Colchicine
Keep reading about Gepotidacin
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