Combination use of beta blockers and calcium channel blockers cause
A. Heart block
B. Hypertension C. Hypotension
D. Bradycardia
E. Tachyarrhythimias
Ans.
A. Heart block ; (D) Bradycardia :
• When β-blockers given
with verapamil or diltiazem, they produce:-
— Additive sinus depression, conduction defects or asystole may occur resulting
in marked bradycardia, A-V block.
— Cardiac arrest may occur.
• Nifedipine causes tachycardia, increased contractility and cardiac output due
to reflex sympathetic stimulation, propranolol has been safely used with
Nifedipine
• Propranolol, initially causes little change in BP (due to blockade of β-mediated
vasodilation but on continued use fall in BP due to chronically reduced CO.).
— Verapamil dilates arterioles and some α-blocking activity — BP is only
moderately lowered.