Drug interactions
Formoterol + Salmeterol
Severity: Major
Formoterol and Salmeterol: 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
Both are long-acting beta-2 agonists, so combining them duplicates therapy and increases adrenergic effects such as tachycardia, tremor, hypertension and hypokalemia. There is no added bronchodilator benefit and the risk of arrhythmia rises.
What this interaction means in plain words
Formoterol and Salmeterol 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; Salmeterol belongs to Respiratory.
Why it happens
Additive beta-2 adrenergic receptor stimulation (therapeutic duplication).
What to do
Avoid concurrent use of two long-acting beta-agonists and use only one. If both were taken, monitor heart rate, blood pressure and potassium.
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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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 Salmeterol
- Ritonavir + Salmeterol Contraindicated
- Salmeterol + Saquinavir Contraindicated
- Amitriptyline + Salmeterol Major
- Arformoterol + Salmeterol Major
- Atazanavir + Salmeterol Major
- Budesonide-formoterol + Salmeterol Major
Frequently asked questions
Can I take Formoterol with Salmeterol?
MediHelp rates the interaction as major. Formoterol and Salmeterol 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. Both are long-acting beta-2 agonists, so combining them duplicates therapy and increases adrenergic effects such as tachycardia, tremor, hypertension and hypokalemia. There is no added bronchodilator benefit and the risk of arrhythmia rises.
How serious is the interaction between Formoterol and Salmeterol?
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 concurrent use of two long-acting beta-agonists and use only one. If both were taken, monitor heart rate, blood pressure and potassium.
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.
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