Drug interactions
Haloperidol + Primaquine
Severity: Major
Haloperidol and Primaquine: 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
Haloperidol is a well-recognized cause of QT prolongation and torsades de pointes, particularly at higher or intravenous doses. Adding primaquine may increase this risk further.
What this interaction means in plain words
Haloperidol and Primaquine 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.
Haloperidol belongs to Central Nervous System; Primaquine belongs to Anti Parasitic.
Why it happens
Additive QTc prolongation through pharmacodynamic effects.
What to do
Obtain a baseline ECG, correct potassium and magnesium, and keep haloperidol at the lowest effective dose. Repeat the ECG during co-therapy and consider an alternative antimalarial if QTc is significantly prolonged.
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 Primaquine
- Pimozide + Primaquine Contraindicated
- Amiodarone + Primaquine Major
- Amisulpride + Primaquine Major
- Anagrelide + Primaquine Major
- Arsenic trioxide + Primaquine Major
- Asenapine + Primaquine Major
Other interactions of Haloperidol
- Dofetilide + Haloperidol Contraindicated
- Dronedarone + Haloperidol Contraindicated
- Haloperidol + Ibutilide Contraindicated
- Haloperidol + Levoketoconazole Contraindicated
- Haloperidol + Panobinostat Contraindicated
- Haloperidol + Pimozide Contraindicated
Frequently asked questions
Can I take Haloperidol with Primaquine?
MediHelp rates the interaction as major. Haloperidol and Primaquine 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. Haloperidol is a well-recognized cause of QT prolongation and torsades de pointes, particularly at higher or intravenous doses. Adding primaquine may increase this risk further.
How serious is the interaction between Haloperidol and Primaquine?
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 a baseline ECG, correct potassium and magnesium, and keep haloperidol at the lowest effective dose. Repeat the ECG during co-therapy and consider an alternative antimalarial if QTc is significantly prolonged.
What other medicines interact with Primaquine?
MediHelp also lists interactions of Primaquine with, for example, Pimozide, Amiodarone, Amisulpride. The full list is on the Primaquine page.
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