Drug interactions
Formoterol + Ibutilide
Severity: Major
Formoterol and Ibutilide: 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
Ibutilide is a potent QT-prolonging antiarrhythmic with a clear risk of torsades de pointes. Formoterol may add to this risk through QT effects, hypokalemia and tachycardia, and the arrhythmia can be life-threatening.
What this interaction means in plain words
Formoterol and Ibutilide 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; Ibutilide belongs to Cardiovascular.
Why it happens
Additive QT prolongation and proarrhythmic effect, with beta-2 agonist induced hypokalemia increasing susceptibility.
What to do
Avoid formoterol around the time of ibutilide administration where possible. If it is unavoidable, correct potassium and magnesium first and maintain continuous ECG monitoring during and after the ibutilide infusion.
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 Ibutilide, 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 Ibutilide
- Amiodarone + Ibutilide Contraindicated
- Amisulpride + Ibutilide Contraindicated
- Chlorpromazine + Ibutilide Contraindicated
- Clarithromycin + Ibutilide Contraindicated
- Desipramine + Ibutilide Contraindicated
- Dolasetron + Ibutilide Contraindicated
Frequently asked questions
Can I take Formoterol with Ibutilide?
MediHelp rates the interaction as major. Formoterol and Ibutilide 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. Ibutilide is a potent QT-prolonging antiarrhythmic with a clear risk of torsades de pointes. Formoterol may add to this risk through QT effects, hypokalemia and tachycardia, and the arrhythmia can be life-threatening.
How serious is the interaction between Formoterol and Ibutilide?
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 formoterol around the time of ibutilide administration where possible. If it is unavoidable, correct potassium and magnesium first and maintain continuous ECG monitoring during and after the ibutilide infusion.
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.
