Drug interactions
Formoterol + Furosemide
Severity: Moderate
Formoterol and Furosemide: moderate 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
Both drugs lower serum potassium, so combined use can produce clinically significant hypokalemia. This is more likely with high formoterol doses and may predispose to arrhythmias, especially in patients with heart disease or taking digoxin.
What this interaction means in plain words
Formoterol and Furosemide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Formoterol belongs to Respiratory; Furosemide belongs to Cardiovascular.
Why it happens
Additive hypokalemia from beta-2 mediated intracellular potassium shift and loop diuretic renal potassium loss.
What to do
Monitor serum potassium and magnesium periodically and replace them as needed. Take particular care in patients with acute severe asthma or COPD exacerbation, where hypoxia worsens the risk.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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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 Furosemide
- Amifostine + Furosemide Major
- Amikacin + Furosemide Major
- Carbenoxolone + Furosemide Major
- Cephaloridine + Furosemide Major
- Cisplatin + Furosemide Major
- Digoxin + Furosemide Major
Frequently asked questions
Can I take Formoterol with Furosemide?
MediHelp rates the interaction as moderate. Formoterol and Furosemide can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Both drugs lower serum potassium, so combined use can produce clinically significant hypokalemia. This is more likely with high formoterol doses and may predispose to arrhythmias, especially in patients with heart disease or taking digoxin.
How serious is the interaction between Formoterol and Furosemide?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor serum potassium and magnesium periodically and replace them as needed. Take particular care in patients with acute severe asthma or COPD exacerbation, where hypoxia worsens the risk.
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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