A calcium channel blocker (CCB) is a chemical that disrupts the movement of calcium (Ca) through calcium channels. CCB drugs devised to target neurons are used as antiepileptics. However, the most widespread clinical usage of calcium channel blockers is to decrease blood pressure in patients with hypertension. CCBs are particularly efficacious in treating elderly patients. Calcium channel blockers are also frequently used to alter heart rate, to prevent cerebral vasospasm, and to reduce chest pain caused by angina pectoris.