Drug interactions
Iloperidone + Ondansetron
Severity: Major
Iloperidone and Ondansetron: major 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
Iloperidone prolongs the QT interval and ondansetron adds to this effect, increasing the risk of torsades de pointes. Patients with bradycardia, hypokalemia or hypomagnesemia are at greater risk.
What this interaction means in plain words
Iloperidone and Ondansetron can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Iloperidone belongs to Central Nervous System; Ondansetron belongs to Gastrointestinal Tract.
Why it happens
Additive QT prolongation through blockade of cardiac potassium channels.
What to do
Use a non-QT-prolonging antiemetic where possible. If both are used, check the ECG and correct potassium and magnesium.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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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 Iloperidone
- Iloperidone + Thioridazine Contraindicated
- Alfuzosin + Iloperidone Major
- Amiodarone + Iloperidone Major
- Amisulpride + Iloperidone Major
- Amitriptyline + Iloperidone Major
- Anagrelide + Iloperidone Major
Frequently asked questions
Can I take Iloperidone with Ondansetron?
MediHelp rates the interaction as major. Iloperidone and Ondansetron can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Iloperidone prolongs the QT interval and ondansetron adds to this effect, increasing the risk of torsades de pointes. Patients with bradycardia, hypokalemia or hypomagnesemia are at greater risk.
How serious is the interaction between Iloperidone and Ondansetron?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use a non-QT-prolonging antiemetic where possible. If both are used, check the ECG and correct potassium and magnesium.
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.
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