Drug interactions
Isoflurane + Ondansetron
Severity: Moderate
Isoflurane and Ondansetron: moderate 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
Volatile anesthetics such as isoflurane can prolong the QT interval. Ondansetron is often given perioperatively, and the combination is common in practice, though it may add to arrhythmia risk in susceptible patients.
What this interaction means in plain words
Isoflurane and Ondansetron can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Isoflurane belongs to Central Nervous System; Ondansetron belongs to Gastrointestinal Tract.
Why it happens
Additive effects on cardiac repolarization.
What to do
Monitor ECG during anesthesia and keep potassium and magnesium in the normal range. Avoid in patients with congenital long QT syndrome and choose a different antiemetic if QTc is markedly prolonged.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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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 Isoflurane
Frequently asked questions
Can I take Isoflurane with Ondansetron?
MediHelp rates the interaction as moderate. Isoflurane and Ondansetron can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Volatile anesthetics such as isoflurane can prolong the QT interval. Ondansetron is often given perioperatively, and the combination is common in practice, though it may add to arrhythmia risk in susceptible patients.
How serious is the interaction between Isoflurane and Ondansetron?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor ECG during anesthesia and keep potassium and magnesium in the normal range. Avoid in patients with congenital long QT syndrome and choose a different antiemetic if QTc is markedly prolonged.
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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