Drug interactions
Formoterol + Spironolactone
Severity: Minor
Formoterol and Spironolactone: minor 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
Formoterol can lower serum potassium, while spironolactone is potassium-sparing and tends to raise it. The effects largely oppose each other, so clinically important change is uncommon, though potassium can still shift in renal impairment or acute illness.
What this interaction means in plain words
Formoterol and Spironolactone have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Formoterol belongs to Respiratory; Spironolactone belongs to Cardiovascular.
Why it happens
Opposing effects on serum potassium: beta2-mediated cellular uptake versus aldosterone antagonism.
What to do
No routine action is needed; monitor potassium in patients with renal impairment, heart failure or on high-dose beta-agonist therapy.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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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 Spironolactone
- Amiloride + Spironolactone Contraindicated
- Eplerenone + Spironolactone Contraindicated
- Spironolactone + Triamterene Contraindicated
- Abiraterone + Spironolactone Major
- Aceclofenac + Spironolactone Major
- Acemetacin + Spironolactone Major
Frequently asked questions
Can I take Formoterol with Spironolactone?
MediHelp rates the interaction as minor. Formoterol and Spironolactone have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Formoterol can lower serum potassium, while spironolactone is potassium-sparing and tends to raise it. The effects largely oppose each other, so clinically important change is uncommon, though potassium can still shift in renal impairment or acute illness.
How serious is the interaction between Formoterol and Spironolactone?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No routine action is needed; monitor potassium in patients with renal impairment, heart failure or on high-dose beta-agonist therapy.
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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