CriticalMacrolide antibiotic×Ergot alkaloid, 5-HT1B/1D and alpha-adrenoceptor agonist
Updated · Methodology
Mechanism
Clarithromycin inhibits CYP3A4 – dihydroergotamine accumulates 5-10 fold. Fatal ergotism.
Symptoms
Limb ischaemia, myocardial infarction.
Management
Combination contraindicated.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Migranal (dihydroergotamine) prescribing information (2020)– FDA Migranal label, Section 4
- AEMPS: Ficha técnica: Claritromicina (nº registro 75638), sección 4.3 (2025)– AEMPS, CIMA, nº registro 75638, revisión 03/2025, sección 4.3