Drug interactions
Granisetron + Trifluoperazine
Severity: Moderate
Granisetron and Trifluoperazine: 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
Trifluoperazine, a phenothiazine antipsychotic, can prolong the QT interval, and granisetron adds a small effect. The combination may increase the risk of torsade de pointes, particularly with electrolyte disturbances or cardiac disease.
What this interaction means in plain words
Granisetron and Trifluoperazine 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.
Why it happens
Additive QT interval prolongation; the legacy statement that both decrease QTc is incorrect.
What to do
Obtain an ECG and correct potassium and magnesium in patients with additional risk factors. Consider another antiemetic when the patient has known QT prolongation.
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 Granisetron
- Apomorphine + Granisetron Contraindicated
- Amiodarone + Granisetron Major
- Amisulpride + Granisetron Major
- Arsenic trioxide + Granisetron Major
- Artemether / lumefantrine + Granisetron Major
- Artemether + Granisetron Major
Frequently asked questions
Can I take Granisetron with Trifluoperazine?
MediHelp rates the interaction as moderate. Granisetron and Trifluoperazine 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. Trifluoperazine, a phenothiazine antipsychotic, can prolong the QT interval, and granisetron adds a small effect. The combination may increase the risk of torsade de pointes, particularly with electrolyte disturbances or cardiac disease.
How serious is the interaction between Granisetron and Trifluoperazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain an ECG and correct potassium and magnesium in patients with additional risk factors. Consider another antiemetic when the patient has known QT prolongation.
What other medicines interact with Granisetron?
MediHelp also lists interactions of Granisetron with, for example, Apomorphine, Amiodarone, Amisulpride. The full list is on the Granisetron page.
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