Clindamycin and Crizotinib: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 1, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Crizotinib
Clindamycin
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.
Let me explain this one simply. Crizotinib (Xalkori) is your cancer medicine, and it can slow down one of your liver's cleanup enzymes (called CYP3A). Clindamycin is an antibiotic that your body partly clears using that same enzyme. When crizotinib slows the cleanup, more clindamycin can build up in your body, which could raise the chance of side effects.
I want to be honest with you: this concern is based on how these drugs are expected to behave, not on strong real-world reports. It doesn't mean anything bad will happen. Your care team can manage this easily by adjusting the dose or watching you a bit more closely. Please just keep taking both as prescribed and check in with your doctor or pharmacist.
Effect: Increased exposure of the CYP3A substrate (clindamycin). Crizotinib is a moderate CYP3A4 inhibitor; inhibition of CYP3A-mediated clindamycin metabolism may raise clindamycin AUC/Cmax.
- Direction: Increased clindamycin effect/toxicity (neither drug is a relevant prodrug here).
- Onset: Unspecified.
- Evidence: Theoretical; severity on file is major.
- Magnitude: Not quantified.
Management: Avoid combination where small concentration increases could cause serious reactions. If unavoidable, consider decreasing the clindamycin (CYP3A substrate) dose and monitor for clindamycin-related adverse effects (GI intolerance, C. difficile risk). Individualize dosing with the care team.
What happens
Increased exposure of the CYP3A substrate
Interaction Deep Dive
Avoid pairing crizotinib, which inhibits CYP3A4, with any CYP3A substrate for which even small shifts in concentration could trigger serious adverse reactions. When such a combination cannot be avoided, reduce the dose of the CYP3A substrate1.
Why it happens (mechanism)
Inhibition of the CYP3A-mediated metabolism of the substrate by crizotinib
How to manage this interaction
Here is how your care team typically handles this:
- They may avoid the combination when a small rise in clindamycin could be risky, or choose an alternative antibiotic.
- If both are needed together, the clindamycin dose may be adjusted and individualized by your care team.
- They may monitor you more closely for antibiotic side effects like stomach upset or diarrhea.
What you should do: keep taking both exactly as prescribed, and let your pharmacist or prescriber know you are on both so they can plan the safest approach. Report any new or worsening side effects promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In a study examining the interaction between crizotinib and midazolam (a CYP3A substrate), taking crizotinib 250 mg twice daily for 28 days together with oral midazolam produced a geometric mean midazolam AUC that was 3.7 times the value observed when midazolam was given by itself 1.
Common questions
Can I take Clindamycin and Crizotinib together?
Crizotinib may raise clindamycin levels and side-effect risk, so tell your care team you take both; they can adjust the dose or watch you more closely. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Clindamycin and Crizotinib 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 Clindamycin and Crizotinib interaction managed?
Here is how your care team typically handles this: They may avoid the combination when a small rise in clindamycin could be risky, or choose an alternative antibiotic. If both are needed together, the clindamycin dose may be adjusted and individualized by your care team. They may monitor you more closely for antibiotic side effects like stomach upset or diarrhea. What you should do: keep taking bo… 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 Clindamycin or Crizotinib 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: XALKORI(R) oral pellets, oral capsules, crizotinib oral pellets, oral capsules. Pfizer Labs (per FDA), New York, NY, 2023. DailyMed
Keep reading about Crizotinib
Keep reading about Clindamycin
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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