CriticalMacrolide antibiotic×Synthetic opioid, full mu-receptor agonist
Updated · Methodology
Mechanism
Clarithromycin inhibits CYP3A4 (raises methadone) and itself prolongs QT. Dual torsades risk in OST patient.
Symptoms
QT above 500 ms, syncope.
Management
Combination contraindicated. Alternative – azithromycin.
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: Methadone hydrochloride tablets (SpecGx) – Prescribing Information (2014)
- AEMPS: Ficha técnica: Metadona (nº registro 62423), sección 4.5 (2026)– AEMPS, CIMA, nº registro 62423, sección 4.5