Drug interactions
Erythromycin ethylsuccinate + Venlafaxine
Severity: Moderate
Erythromycin ethylsuccinate and Venlafaxine: 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
Erythromycin prolongs the QT interval and venlafaxine may add to this effect. Erythromycin also inhibits CYP3A4, which can modestly increase venlafaxine levels, raising the risk of arrhythmia.
What this interaction means in plain words
Erythromycin ethylsuccinate and Venlafaxine 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
Additive QT prolongation, plus CYP3A4 inhibition by erythromycin reducing venlafaxine clearance.
What to do
Consider an alternative antibiotic with less QT effect. If used, check electrolytes, monitor the ECG in patients with cardiac risk factors, and watch for venlafaxine adverse effects.
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 Venlafaxine
- Isocarboxazid + Venlafaxine Contraindicated
- Methylene blue + Venlafaxine Contraindicated
- Phenelzine + Venlafaxine Contraindicated
- Procarbazine + Venlafaxine Contraindicated
- Rasagiline + Venlafaxine Contraindicated
- Safinamide + Venlafaxine Contraindicated
Frequently asked questions
Can I take Erythromycin ethylsuccinate with Venlafaxine?
MediHelp rates the interaction as moderate. Erythromycin ethylsuccinate and Venlafaxine 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. Erythromycin prolongs the QT interval and venlafaxine may add to this effect. Erythromycin also inhibits CYP3A4, which can modestly increase venlafaxine levels, raising the risk of arrhythmia.
How serious is the interaction between Erythromycin ethylsuccinate and Venlafaxine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Consider an alternative antibiotic with less QT effect. If used, check electrolytes, monitor the ECG in patients with cardiac risk factors, and watch for venlafaxine adverse effects.
What other medicines interact with Venlafaxine?
MediHelp also lists interactions of Venlafaxine with, for example, Isocarboxazid, Methylene blue, Phenelzine. The full list is on the Venlafaxine page.
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