Ceritinib and Clindamycin: 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
Ceritinib
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.
You've been prescribed ceritinib (a cancer medicine) and clindamycin (an antibiotic). Ceritinib can slow down a liver enzyme called CYP3A that helps your body break down clindamycin. When that enzyme is slowed, clindamycin can build up higher than usual, which may lead to more side effects (for example, stomach upset or diarrhea).
I want to be clear that this concern is based on how these drugs are expected to behave, not on strong real-world studies. Please don't stop or change either medicine on your own. The good news is your care team can manage this by adjusting your dose if needed and watching you a little more closely. Just check in with your pharmacist or doctor.
Effect: Increased exposure of the CYP3A substrate (clindamycin) via ceritinib-mediated CYP3A inhibition. Clindamycin is partially metabolized by CYP3A4; reduced clearance may raise its plasma concentrations and adverse-effect potential.
- Direction: Increased clindamycin exposure (AUC/Cmax); neither agent is a prodrug requiring activation.
- Severity: Major. Evidence: Theoretical. Onset: Unspecified.
- Management: Avoid concomitant use where the CYP3A substrate has a narrow therapeutic index. If co-administration is unavoidable, consider dose reduction of the substrate and monitor for concentration-dependent toxicity (GI effects, diarrhea/colitis).
What happens
Increased exposure of CYP3A substrate
Interaction Deep Dive
The combination of ceritinib with a CYP3A substrate that has a narrow therapeutic index should be avoided, since doing so can raise the substrate's exposure and its adverse effects. When such concurrent administration is unavoidable, reducing the dose of the CYP3A substrate should be considered1.
Why it happens (mechanism)
Inhibition of CYP3A-mediated metabolism by ceritinib
How to manage this interaction
Both medicines can usually be handled safely with a little planning from your care team.
- Keep taking both as prescribed unless your doctor or pharmacist tells you otherwise.
- Your team may lower the clindamycin dose or watch you more closely for side effects while you're on both.
- In some cases they may choose a different antibiotic if one fits better.
- Tell your prescriber about any diarrhea, stomach pain, or new symptoms, especially severe or ongoing diarrhea.
Bring up this combination at your next visit or call your pharmacy so your dose can be adjusted and individualized for you.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Ceritinib and Clindamycin together?
Ceritinib can slow the breakdown of clindamycin and raise its levels, so keep taking both as prescribed but ask your care team whether your clindamycin dose should be adjusted or monitored more closely. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ceritinib and Clindamycin 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 Ceritinib and Clindamycin interaction managed?
Both medicines can usually be handled safely with a little planning from your care team. Keep taking both as prescribed unless your doctor or pharmacist tells you otherwise. Your team may lower the clindamycin dose or watch you more closely for side effects while you're on both. In some cases they may choose a different antibiotic if one fits better. Tell your prescriber about any diarrhea, stomac… 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 Ceritinib or Clindamycin 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: ZYKADIA(TM) oral capsules, ceritinib oral capsules. Novartis Pharmaceuticals Corporation (per FDA), East Hanover, NJ, 2014. DailyMed
Keep reading about Ceritinib
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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