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[Carbamazepine and clarithromycin: a clinically relevant drug interaction]
P Gélisse1, D Hillaire-Buys, E Halaili
1Unité Médico-Chirurgicale de l'Epilepsie, Hôpital Gui-de-Chauliac, Montpellier. p-gelisse@chu-montpellier.fr
Revue Neurologique
|November 23, 2007
Summary
Carbamazepine and clarithromycin can interact, leading to carbamazepine overdosage. Clarithromycin inhibits carbamazepine metabolism, so avoid this combination in patients.
Area of Science:
- Pharmacology
- Drug Metabolism
- Drug Interactions
Background:
- Carbamazepine (CBZ) is known to interact with macrolide antibiotics that inhibit its metabolism.
- Clarithromycin (CLA), a macrolide antibiotic, is frequently prescribed for respiratory infections and H. pylori eradication.
Observation:
- This study investigated the interaction between CBZ and CLA.
- Data from three epilepsy patients and seven reported cases were analyzed.
Findings:
- Co-administration of CLA with CBZ resulted in transient CBZ overdosage.
- Symptoms included ataxia, dizziness, diplopia, nausea, vomiting, and drowsiness.
- Elevated CBZ blood levels (13.3–28.5 mg/l) were observed in eight patients.
Implications:
- Clarithromycin inhibits the cytochrome P450 3A4 (CYP3A4)-mediated metabolism of carbamazepine.
- This drug interaction necessitates caution and avoidance of clarithromycin in patients taking carbamazepine.
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