Drug interactions
Arformoterol + Erythromycin
Severity: Moderate
Arformoterol and Erythromycin: 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 can prolong the QT interval, and beta-agonists may also lower potassium and raise heart rate. Together they may add to the risk of ventricular arrhythmias, including torsade de pointes, particularly in patients with other risk factors.
What this interaction means in plain words
Arformoterol and Erythromycin 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.
Arformoterol belongs to Respiratory; Erythromycin belongs to Anti Bacterial.
Why it happens
Additive QT prolongation from macrolide hERG channel blockade and beta-agonist effects including hypokalemia and tachycardia.
What to do
Check baseline QTc and electrolytes in patients with cardiac risk factors and correct potassium and magnesium. Consider an alternative antibiotic such as doxycycline if QT risk is high.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Arformoterol and Erythromycin, 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.
Other interactions of Erythromycin
- Conivaptan + Erythromycin Contraindicated
- Dihydroergotamine intranasal + Erythromycin Contraindicated
- Dihydroergotamine + Erythromycin Contraindicated
- Domperidone + Erythromycin Contraindicated
- Dronedarone + Erythromycin Contraindicated
- Droperidol + Erythromycin Contraindicated
Other interactions of Arformoterol
Frequently asked questions
Can I take Arformoterol with Erythromycin?
MediHelp rates the interaction as moderate. Arformoterol and Erythromycin 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 can prolong the QT interval, and beta-agonists may also lower potassium and raise heart rate. Together they may add to the risk of ventricular arrhythmias, including torsade de pointes, particularly in patients with other risk factors.
How serious is the interaction between Arformoterol and Erythromycin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check baseline QTc and electrolytes in patients with cardiac risk factors and correct potassium and magnesium. Consider an alternative antibiotic such as doxycycline if QT risk is high.
What other medicines interact with Erythromycin?
MediHelp also lists interactions of Erythromycin with, for example, Conivaptan, Dihydroergotamine intranasal, Dihydroergotamine. The full list is on the Erythromycin 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.
