Drug interactions
Nelfinavir + Ondansetron
Severity: Minor
Nelfinavir and Ondansetron: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Nelfinavir inhibits CYP3A4 and may modestly raise ondansetron concentrations. Because other enzymes also clear ondansetron, the effect is usually small.
What this interaction means in plain words
Nelfinavir and Ondansetron have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Nelfinavir belongs to Anti Virals; Ondansetron belongs to Gastrointestinal Tract.
Why it happens
CYP3A4 inhibition by nelfinavir reduces one pathway of ondansetron clearance.
What to do
No dose adjustment is generally required. Obtain an ECG if other QT-prolonging factors are present.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Nelfinavir and Ondansetron, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Ondansetron
- Apomorphine + Ondansetron Contraindicated
- Ondansetron + Thioridazine Contraindicated
- Ondansetron + Vandetanib Contraindicated
- Adagrasib + Ondansetron Major
- Amiodarone + Ondansetron Major
- Amisulpride + Ondansetron Major
Other interactions of Nelfinavir
- Alfuzosin + Nelfinavir Contraindicated
- Avanafil + Nelfinavir Contraindicated
- Dronedarone + Nelfinavir Contraindicated
- Eletriptan + Nelfinavir Contraindicated
- Ergotamine + Nelfinavir Contraindicated
- Flibanserin + Nelfinavir Contraindicated
Frequently asked questions
Can I take Nelfinavir with Ondansetron?
MediHelp rates the interaction as minor. Nelfinavir and Ondansetron have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Nelfinavir inhibits CYP3A4 and may modestly raise ondansetron concentrations. Because other enzymes also clear ondansetron, the effect is usually small.
How serious is the interaction between Nelfinavir and Ondansetron?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No dose adjustment is generally required. Obtain an ECG if other QT-prolonging factors are present.
What other medicines interact with Ondansetron?
MediHelp also lists interactions of Ondansetron with, for example, Apomorphine, Thioridazine, Vandetanib. The full list is on the Ondansetron page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
