Aprepitant and Ondansetron interaction
Aprepitant and Ondansetron: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Ondansetron label · effective 2026-04-16
Phenytoin, Carbamazepine, and Rifampin In patients treated with potent inducers of CYP3A4 (i.e., phenytoin, carbamazepine, and rifampin), the clearance of ondansetron was significantly increased and ondansetron blood concentrations were decreased.
From the Aprepitant (CINVANTI) label · effective 2026-04-01
Examples ondansetron, granisetron, dolasetron 7.2 Effect of Other Drugs on the Pharmacokinetics of Aprepitant Aprepitant is a CYP3A4 substrate [see Clinical Pharmacology (12.3) ] .
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.