MajorCalcium channel blocker, non-DHP (benzothiazepine derivative)×Non-selective beta blocker
Updated · Methodology
Mechanism
Non-dihydropyridine calcium channel blocker (diltiazem) + non-selective beta-blocker (propranolol) – marked additive bradycardia, AV block, negative inotropic effect. Risk of symptomatic AV block, especially in older patients and left ventricular dysfunction.
Symptoms
Bradycardia (heart rate below 50/min), dizziness, syncope. ECG: first- to second-degree AV block. Older patients: fall risk.
Management
Avoid the combination. For atrial fibrillation rate control, propranolol + digoxin (without diltiazem) or diltiazem with propranolol withdrawn. In heart failure, a selective beta-blocker (bisoprolol) or carvedilol is preferable.
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: Cardizem section 7 (2014)– ; DailyMed setid f3e7ecef-f360-4987-a4f5-933214130ab2
- AEMPS: Ficha técnica: Propranolol (nº registro 89692), sección 4.5 (2026)– AEMPS, CIMA, nº registro 89692, revisión 05/2026, sección 4.5