Drug interactions
Lisdexamfetamine + Pimozide
Severity: Major
Lisdexamfetamine and Pimozide: major 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
Pimozide is a dopamine antagonist used in Tourette disorder, and stimulants can worsen tics and oppose its action. Pimozide also prolongs the QT interval, and stimulant-induced tachycardia and sympathetic activation may increase arrhythmic risk. Labeling for pimozide advises caution with stimulants.
What this interaction means in plain words
Lisdexamfetamine and Pimozide 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.
Lisdexamfetamine belongs to Central Nervous System; Pimozide belongs to Central Nervous System.
Why it happens
Opposing dopaminergic effects plus additive cardiac risk from pimozide QT prolongation and amphetamine sympathomimetic action.
What to do
Avoid if possible; if combined, obtain a baseline and follow-up ECG and monitor tics and heart rate. Keep electrolytes normal and avoid other QT-prolonging drugs.
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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Other interactions of Lisdexamfetamine
- Isocarboxazid + Lisdexamfetamine Contraindicated
- Linezolid + Lisdexamfetamine Contraindicated
- Lisdexamfetamine + Phenelzine Contraindicated
- Lisdexamfetamine + Procarbazine Contraindicated
- Lisdexamfetamine + Rasagiline Contraindicated
- Lisdexamfetamine + Safinamide Contraindicated
Other interactions of Pimozide
- Adagrasib + Pimozide Contraindicated
- Amiodarone + Pimozide Contraindicated
- Amisulpride + Pimozide Contraindicated
- Amitriptyline + Pimozide Contraindicated
- Amoxapine + Pimozide Contraindicated
- Anagrelide + Pimozide Contraindicated
Frequently asked questions
Can I take Lisdexamfetamine with Pimozide?
MediHelp rates the interaction as major. Lisdexamfetamine and Pimozide 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. Pimozide is a dopamine antagonist used in Tourette disorder, and stimulants can worsen tics and oppose its action. Pimozide also prolongs the QT interval, and stimulant-induced tachycardia and sympathetic activation may increase arrhythmic risk. Labeling for pimozide advises caution with stimulants.
How serious is the interaction between Lisdexamfetamine and Pimozide?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid if possible; if combined, obtain a baseline and follow-up ECG and monitor tics and heart rate. Keep electrolytes normal and avoid other QT-prolonging drugs.
What other medicines interact with Lisdexamfetamine?
MediHelp also lists interactions of Lisdexamfetamine with, for example, Isocarboxazid, Linezolid, Phenelzine. The full list is on the Lisdexamfetamine page.
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