Major
Metoprolol × Verapamil
Selective β1-adrenoceptor blockers×Non-dihydropyridine calcium channel blocker
Mechanism
Verapamil and metoprolol slow AV conduction via independent paths. Additive – severe bradycardia, AV block, asystole. Verapamil also inhibits CYP2D6 (metoprolol metabolism) – level rises.
Symptoms
Bradycardia below 50, AV block, hypotension.
Management
Avoid combination. Alternative – amlodipine (no AV node effect).
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.