Short-acting and long-acting calcium channel blockers differ in their chemical structure and their preference for specific types of calcium channels, according to Richard E. Klabunde, Ph.D. Dihydropyridine drugs are selective for vascular calcium channels and are short-acting agents, while benzothiazepine and phenylalkylamine drugs are more selective for calcium channels in the myocardium of the heart and are long-acting drugs.Continue Reading
Only two long-acting cardiac channel blockers are in wide clinical use, writes Dr. Klabunde. These are benzothiazepine diltiazem and phenylalkylamine verapamil. The selectivity of verapamil for myocardial calcium channels is considerably higher than that of short-acting calcium channel blockers, while dilitazem is less selective than verapamil but more selective than the dihydropyridines. There is a large variety of short-acting agents that doctors use clinically that includes amlodipine, felodipine and nimodipine, in contrast to the few long-acting calcium channel blockers.
Clinically, doctors often use verapamil to treat angina, while they use diltiazem and short-acting calcium channel blockers to treat hypertension, according to Dr. Klabunde. One potential advantage of using dilitazem is that its additional effects on myocardial calcium channels can help reduce the increase in reflex cardiac stimulation and heart rate that often occur as side effects of short-acting calcium channel blockers. A study comparing mortality rates among patients prescribed long-acting or short-acting agents after a heart attack showed a significant reduction in mortality among those prescribed long-acting drugs, according to the Journal of the American Geriatrics Society.Learn more about Medications & Vitamins