Drug interactions
Erythromycin + Loratadine
Severity: Minor
Erythromycin and Loratadine: 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
Erythromycin raises loratadine and desloratadine concentrations. Clinically significant QT changes or adverse events have generally not been observed at standard doses.
What this interaction means in plain words
Erythromycin and Loratadine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Erythromycin belongs to Anti Bacterial; Loratadine belongs to Respiratory.
Why it happens
Erythromycin inhibits CYP3A4 and P-glycoprotein, reducing loratadine metabolism.
What to do
No dose adjustment is normally needed. Be aware of increased sedation or palpitations, and consider an alternative antihistamine if symptoms occur.
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 Erythromycin
- Conivaptan + Erythromycin Contraindicated
- Dihydroergotamine intranasal + Erythromycin Contraindicated
- Dihydroergotamine + Erythromycin Contraindicated
- Domperidone + Erythromycin Contraindicated
- Dronedarone + Erythromycin Contraindicated
- Droperidol + Erythromycin Contraindicated
Other interactions of Loratadine
- Acrivastine + Loratadine Moderate
- Amobarbital + Loratadine Moderate
- Fentanyl + Loratadine Moderate
- Isocarboxazid + Loratadine Moderate
- Levoketoconazole + Loratadine Moderate
- Loratadine + Mavacamten Moderate
Frequently asked questions
Can I take Erythromycin with Loratadine?
MediHelp rates the interaction as minor. Erythromycin and Loratadine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Erythromycin raises loratadine and desloratadine concentrations. Clinically significant QT changes or adverse events have generally not been observed at standard doses.
How serious is the interaction between Erythromycin and Loratadine?
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 dose adjustment is normally needed. Be aware of increased sedation or palpitations, and consider an alternative antihistamine if symptoms occur.
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.
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