Drug interactions
Ondansetron + Sertraline
Severity: Moderate
Ondansetron and Sertraline: 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
Both drugs can prolong the QT interval, and ondansetron has also been associated with serotonin syndrome when used with SSRIs such as sertraline. Sertraline has a relatively small QT effect, so the overall risk is modest but increases with other risk factors.
What this interaction means in plain words
Ondansetron and Sertraline 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.
Ondansetron belongs to Gastrointestinal Tract; Sertraline belongs to Central Nervous System.
Why it happens
Additive effects on cardiac repolarization plus possible additive serotonergic activity.
What to do
Correct electrolytes and obtain an ECG in patients with cardiac risk factors. Counsel patients to report symptoms of serotonin toxicity such as agitation, tremor or fever.
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 Sertraline
- Isocarboxazid + Sertraline Contraindicated
- Methylene blue + Sertraline Contraindicated
- Phenelzine + Sertraline Contraindicated
- Pimozide + Sertraline Contraindicated
- Selegiline transdermal + Sertraline Contraindicated
- Selegiline + Sertraline Contraindicated
Frequently asked questions
Can I take Ondansetron with Sertraline?
MediHelp rates the interaction as moderate. Ondansetron and Sertraline 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. Both drugs can prolong the QT interval, and ondansetron has also been associated with serotonin syndrome when used with SSRIs such as sertraline. Sertraline has a relatively small QT effect, so the overall risk is modest but increases with other risk factors.
How serious is the interaction between Ondansetron and Sertraline?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Correct electrolytes and obtain an ECG in patients with cardiac risk factors. Counsel patients to report symptoms of serotonin toxicity such as agitation, tremor or fever.
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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