Drug interactions
Fenfluramine + Pimozide
Severity: Moderate
Fenfluramine and Pimozide: 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
Fenfluramine is a serotonergic agent that can cause somnolence and, rarely, serotonin syndrome, while pimozide can cause sedation and has dopamine-blocking effects. Combined use may produce unpredictable CNS effects, and both can affect cardiac function (fenfluramine is associated with valvular heart disease and pulmonary hypertension).
What this interaction means in plain words
Fenfluramine and Pimozide 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.
Fenfluramine belongs to Central Nervous System; Pimozide belongs to Central Nervous System.
Why it happens
Combined serotonergic and dopamine-blocking pharmacodynamic effects on the CNS; the overall net effect is not well characterized.
What to do
Monitor for sedation, agitation, hyperthermia and other signs of serotonin toxicity or NMS. Keep up the echocardiographic and ECG monitoring that fenfluramine therapy requires.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Fenfluramine and Pimozide, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Pimozide
- Adagrasib + Pimozide Contraindicated
- Amiodarone + Pimozide Contraindicated
- Amisulpride + Pimozide Contraindicated
- Amitriptyline + Pimozide Contraindicated
- Amoxapine + Pimozide Contraindicated
- Anagrelide + Pimozide Contraindicated
Other interactions of Fenfluramine
- Fenfluramine + Isocarboxazid Contraindicated
- Fenfluramine + Linezolid Contraindicated
- Fenfluramine + Phenelzine Contraindicated
- Fenfluramine + Selegiline Contraindicated
- Fenfluramine + Tranylcypromine Contraindicated
- Almotriptan + Fenfluramine Major
Frequently asked questions
Can I take Fenfluramine with Pimozide?
MediHelp rates the interaction as moderate. Fenfluramine and Pimozide 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. Fenfluramine is a serotonergic agent that can cause somnolence and, rarely, serotonin syndrome, while pimozide can cause sedation and has dopamine-blocking effects. Combined use may produce unpredictable CNS effects, and both can affect cardiac function (fenfluramine is associated with valvular heart disease and pulmonary hypertension).
How serious is the interaction between Fenfluramine and Pimozide?
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 for sedation, agitation, hyperthermia and other signs of serotonin toxicity or NMS. Keep up the echocardiographic and ECG monitoring that fenfluramine therapy requires.
What other medicines interact with Pimozide?
MediHelp also lists interactions of Pimozide with, for example, Adagrasib, Amiodarone, Amisulpride. The full list is on the Pimozide page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
