Drug interactions
Formoterol + Methyclothiazide
Severity: Moderate
Formoterol and Methyclothiazide: 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 formoterol and thiazide diuretics can lower serum potassium. Together they may cause clinically significant hypokalemia, increasing the risk of arrhythmias.
What this interaction means in plain words
Formoterol and Methyclothiazide 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.
Why it happens
Beta-2 stimulated intracellular potassium shift combined with thiazide renal potassium loss.
What to do
Monitor serum potassium and magnesium, especially at initiation and in patients with heart disease, and supplement as needed.
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
Frequently asked questions
Can I take Formoterol with Methyclothiazide?
MediHelp rates the interaction as moderate. Formoterol and Methyclothiazide 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 formoterol and thiazide diuretics can lower serum potassium. Together they may cause clinically significant hypokalemia, increasing the risk of arrhythmias.
How serious is the interaction between Formoterol and Methyclothiazide?
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, especially at initiation and in patients with heart disease, and supplement as needed.
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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