Abemaciclib and Netupitant: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 10, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Netupitant
No brand names on recordAbemaciclib
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's talk about taking abemaciclib (Verzenio) and netupitant together. Netupitant, which is often used to prevent nausea from chemotherapy, can slow down the liver enzyme that normally clears abemaciclib out of your body. When that clearing slows down, the level of abemaciclib in your blood can rise a bit higher than usual.
What that means for you is a possible increase in abemaciclib's side effects, like diarrhea, tiredness, or low blood counts. This is based mostly on theory rather than lots of real-world reports, so please don't be alarmed. Your cancer care team can manage this easily by adjusting your dose or watching you a little more closely. Keep taking both as prescribed and check in with them.
Effect: Netupitant (moderate CYP3A4 inhibitor) may reduce CYP3A4-mediated metabolism of abemaciclib (CYP3A4 substrate), increasing plasma levels of abemaciclib and its active metabolites and raising toxicity risk.
- Direction: Increased abemaciclib exposure. Neither drug is a prodrug requiring activation here.
- Evidence: Theoretical; severity moderate; onset unspecified.
- Management: Avoid concurrent use for 1 week. If use within 1 week is necessary, consider reducing the abemaciclib dose. If coadministered, monitor for adverse reactions and reduce abemaciclib in 50 mg increments per labeling (e.g., 150 mg BID to 100 mg BID, then 50 mg BID; discontinue if 50 mg BID not tolerated).
What happens
Increased abemaciclib plasma concentration
Interaction Deep Dive
Taking abemaciclib (which is a CYP3A4 substrate) together with netupitant (a moderate CYP3A4 inhibitor) can raise the plasma concentrations of both abemaciclib and its active metabolite, potentially heightening toxicity1. For a period of 1 week, avoid using abemaciclib alongside netupitant; should abemaciclib administration be required within that 1-week window of netupitant, a reduced abemaciclib dose should be considered2. When the two are given together, watch for adverse reactions and think about lowering the abemaciclib dose in 50-mg steps. For patients on 150 mg twice daily: reduce first to 100 mg twice daily, then to 50 mg twice daily as a second step, and stop the drug if 50 mg twice daily cannot be tolerated. For patients on 200 mg twice daily: reduce first to 150 mg twice daily, next to 100 mg twice daily, then to 50 mg twice daily as a third step, and discontinue if 50 mg twice daily is not tolerated1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated abemaciclib metabolism
How to manage this interaction
This interaction is manageable, and both medications can still have a place in your treatment. Your care team decides the right approach based on your situation.
- Keep taking both as prescribed unless your oncologist or pharmacist tells you otherwise.
- Your team may space the medications apart (often avoiding overlap by about a week when possible).
- Your abemaciclib dose may be adjusted and individualized in 50 mg steps if the drugs are used together.
- Your team may monitor you more closely for side effects like diarrhea, fatigue, or infection.
Tell your pharmacist or prescriber about any new nausea medicine and report worsening side effects promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) Drug interaction studies predict that giving abemaciclib together with verapamil and diltiazem (moderate CYP3A inhibitors) will raise the AUC of abemaciclib along with its active metabolites (M2, M18, and M20) by roughly 1.6-fold and 2.4-fold, respectively 1.
Common questions
Can I take Abemaciclib and Netupitant together?
Netupitant can raise abemaciclib levels and its side effects, so your care team may adjust the abemaciclib dose or monitor you more closely; keep taking both as prescribed and report any new or worsening side effects. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Abemaciclib and Netupitant interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Abemaciclib and Netupitant interaction managed?
This interaction is manageable, and both medications can still have a place in your treatment. Your care team decides the right approach based on your situation. Keep taking both as prescribed unless your oncologist or pharmacist tells you otherwise. Your team may space the medications apart (often avoiding overlap by about a week when possible). Your abemaciclib dose may be adjusted and individua… 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 Abemaciclib or Netupitant 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 anything you'd monitor while I'm on both?
References (2)
Keep reading about Netupitant
Keep reading about Abemaciclib
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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