Verapamil

Indications angina, tachyarrhythmias
Mechanism of action - non-dihydropyridine CCB
- blocks L-type voltage gated Ca channels = prevents intracellular Ca influx
- slows AV node conduction
Net effect - negative inotropy
- negative chronotropy
- negative dromotropy (AV node blockade)
- peripheral vasodilatation; vascular smooth muscle relaxation
Dose
Pharmacokinetics Absorption high 1st pass effect
Distribution high plasma protein binding
Metabolism: t½ 6-8h
Elimination
Time course of action
Adverse effects heart failure, hypotension, bradycardia, heart block
Contraindications beta blocker use!!
WPW, accessory conducting pathways causing AF or flutter
2nd/3rd degree AV block, sick sinus, SAN block