Venetoclax 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
Venetoclax
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.
Here's what's going on. Venetoclax (Venclexta) can block a transporter in your body called P-gp. Colchicine relies on that same transporter to be moved out of your cells and cleared. When venetoclax slows it down, more colchicine can build up in your body.
Colchicine already has a narrow safety window, so higher levels can mean more side effects like nausea, diarrhea, stomach cramps, or muscle problems. The good news is that this concern is mostly theoretical, and your care team can manage it easily by adjusting timing or watching you a little more closely. Please don't change either medicine on your own, just check in with your pharmacist or doctor.
Mechanism: Venetoclax inhibits intestinal P-glycoprotein (P-gp). Colchicine is a P-gp substrate, so inhibition can increase colchicine exposure (higher Cmax/AUC) and the risk of dose-related toxicity (GI effects, myelosuppression, neuromuscular toxicity).
Direction: Increased colchicine effect/toxicity. Neither is a prodrug here.
Evidence: Theoretical for colchicine; extrapolated from a PK study where single-dose venetoclax 100 mg raised digoxin Cmax ~35% and AUC ~9%.
- Colchicine is narrow therapeutic index, so even modest exposure increases matter.
- Avoid coadministration if possible.
- If needed, give colchicine at least 6 hours before venetoclax; monitor for toxicity.
- Use added caution in renal or hepatic impairment.
What happens
Increased exposure of P-gp substrate and an increased toxicities of these substrates
Interaction Deep Dive
Concurrent use of venetoclax with P-gp substrates should be avoided, since exposure to the P-gp substrate can rise, potentially heightening the toxicities associated with those substrates. A pharmacokinetic study showed that giving a single 100 mg dose of venetoclax together with 0.5 mg of digoxin (a P-gp substrate) raised digoxin Cmax by 35% and AUC(0-inf) by 9%. When simultaneous administration cannot be avoided, the P-gp substrate should be given no less than 6 hours prior to venetoclax1.
Why it happens (mechanism)
Inhibition of P-gp substrate metabolism by venetoclax
How to manage this interaction
What your care team may do:
- Try to avoid using these two together when there is a good alternative.
- If both are needed, separate the timing, typically giving colchicine at least 6 hours before venetoclax.
- Watch you more closely for colchicine side effects, and your colchicine dose may be adjusted and individualized to keep you safe.
What you should do: Keep taking both exactly as prescribed unless your team tells you otherwise. Let your pharmacist or doctor know about new or worsening diarrhea, vomiting, muscle weakness or pain, numbness, or signs of infection, and confirm the best timing for your doses.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In a pharmacokinetic study, giving a single 100 mg dose of venetoclax together with 0.5 mg of digoxin (a P-gp substrate) raised the digoxin Cmax by 35% and the AUC(0-inf) by 9% 1.
Common questions
Can I take Venetoclax and Colchicine together?
Venetoclax can raise colchicine levels and side effects, so avoid the combination if possible; if both are needed, take colchicine at least 6 hours before venetoclax and watch for colchicine toxicity. Talk to your pharmacist or doctor before making any changes. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Venetoclax and Colchicine 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 Venetoclax and Colchicine interaction managed?
What your care team may do: Try to avoid using these two together when there is a good alternative. If both are needed, separate the timing, typically giving colchicine at least 6 hours before venetoclax. Watch you more closely for colchicine side effects, and your colchicine dose may be adjusted and individualized to keep you safe. What you should do: Keep taking both exactly as prescribed unless… 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 Venetoclax 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 (1)
- Product Information: VENCLEXTA(R) oral tablets, venetoclax oral tablets. AbbVie Inc (per FDA), North Chicago, IL, 2022. DailyMed
Keep reading about Venetoclax
Keep reading about Colchicine
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