Calcium Channel Blockers

Original Editor - Lucinda hampton

Top Contributors - Lucinda hampton, Wajeeha Hassan and Kim Jackson  

Introduction

CCB in a cell membrane.

Calcium channel blockers (CCBs) are used in the management of hypertension, angina pectoris, supraventricular arrhythmias, subarachnoid hemorrhage, pulmonary hypertension, and for the prevention of migraine.

They work by preventing calcium from entering the cells of the heart and arteries. Calcium causes the heart and arteries to contract more strongly. By blocking calcium, calcium channel blockers allow blood vessels to relax and open.

Some calcium channel blockers can also slow the heart rate, which can further lower blood pressure.

Categories

CCBs are often classify into two major categories, either non-dihydropyridines or dihydropyridines, based on their primary physiologic effects.

1. The non-dihydropyridines have inhibitory effects on the sinoatrial (SA), and atrioventricular (AV) nodes resulting in a slowing of cardiac conduction and contractility. The are useful for the treatment of hypertension, reducing oxygen demand, and helps to control the rate in tachycardia.
2. The dihydropyridines have a little direct effect on the myocardium, and instead, are more often peripheral vasodilators, and are useful for hypertension, post-intracranial hemorrhage associated vasospasm, and migraines.

Adverse Effects

Ethanol blocks voltage-gated CC

Non-dihydropyridines may cause constipation, worsening cardiac output, and bradycardia.

Dihydropyridines may lead to lightheadedness, flushing, headaches, and peripheral edema.

Alcohol, combined with a calcium channel blocker, can cause severe side effects and may also affect the way the medication works.