Drug interactions
Flecainide + Granisetron
Severity: Major
Flecainide and Granisetron: major interaction.
Last updated Sources: US FDA label
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
Flecainide slows cardiac conduction and can be proarrhythmic, and granisetron can add modest QT prolongation. The combination may increase the risk of serious ventricular arrhythmia, particularly in patients with structural heart disease.
What this interaction means in plain words
Flecainide and Granisetron 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.
Flecainide belongs to Cardiovascular; Granisetron belongs to Gastrointestinal Tract.
Why it happens
Additive effects on cardiac conduction and repolarisation (sodium channel blockade plus QT prolongation).
What to do
Obtain an ECG before and during therapy and correct electrolytes. Consider an antiemetic with less cardiac effect in patients with heart disease.
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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References
Other interactions of Granisetron
- Apomorphine + Granisetron Contraindicated
- Amiodarone + Granisetron Major
- Amisulpride + Granisetron Major
- Arsenic trioxide + Granisetron Major
- Artemether / lumefantrine + Granisetron Major
- Artemether + Granisetron Major
Other interactions of Flecainide
- Flecainide + Nirmatrelvir Contraindicated
- Flecainide + Nirmatrelvir / ritonavir Contraindicated
- Flecainide + Pimozide Contraindicated
- Flecainide + Ritonavir Contraindicated
- Flecainide + Thioridazine Contraindicated
- Flecainide + Tipranavir Contraindicated
Frequently asked questions
Can I take Flecainide with Granisetron?
MediHelp rates the interaction as major. Flecainide and Granisetron 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. Flecainide slows cardiac conduction and can be proarrhythmic, and granisetron can add modest QT prolongation. The combination may increase the risk of serious ventricular arrhythmia, particularly in patients with structural heart disease.
How serious is the interaction between Flecainide and Granisetron?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain an ECG before and during therapy and correct electrolytes. Consider an antiemetic with less cardiac effect in patients with heart disease.
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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