Drug interactions
Formoterol + Haloperidol
Severity: Major
Formoterol and Haloperidol: 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
Haloperidol carries a recognized risk of QT prolongation and torsades de pointes, and formoterol can add to this through its own effects on QT and potassium. The combination may increase proarrhythmic risk, especially with intravenous or high-dose haloperidol.
What this interaction means in plain words
Formoterol and Haloperidol 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.
Formoterol belongs to Respiratory; Haloperidol belongs to Central Nervous System.
Why it happens
Additive QT prolongation, with beta-2 agonist induced hypokalemia increasing susceptibility to arrhythmia.
What to do
Obtain a baseline and follow-up ECG and correct potassium and magnesium before and during therapy. Avoid the combination in patients with long QT or other risk factors, or select a non-QT-prolonging alternative.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Formoterol and Haloperidol, 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 7 days on the web. No card needed.
References
Other interactions of Formoterol
- Adagrasib + Formoterol Major
- Amiodarone + Formoterol Major
- Amisulpride + Formoterol Major
- Amitriptyline + Formoterol Major
- Amoxapine + Formoterol Major
- Arformoterol + Formoterol 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 Formoterol with Haloperidol?
MediHelp rates the interaction as major. Formoterol and Haloperidol 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 carries a recognized risk of QT prolongation and torsades de pointes, and formoterol can add to this through its own effects on QT and potassium. The combination may increase proarrhythmic risk, especially with intravenous or high-dose haloperidol.
How serious is the interaction between Formoterol and Haloperidol?
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 and follow-up ECG and correct potassium and magnesium before and during therapy. Avoid the combination in patients with long QT or other risk factors, or select a non-QT-prolonging alternative.
What other medicines interact with Formoterol?
MediHelp also lists interactions of Formoterol with, for example, Adagrasib, Amiodarone, Amisulpride. The full list is on the Formoterol 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.
