European physicians often prescribe the calcium channel blocker, manidipine, for the treatment of mild to moderate high blood pressure. A comparable medication that is often prescribed in the United States is nifedipine. There are three types of calcium channel blocker, and each interferes with calcium ion flow in a different way and in different calcium paths. Some of these medications affect the heart more than others. As a whole, manidipine and other calcium channel blocking medications share similar properties and side effects.
Manidipine belongs to the class of calcium channel blockers known as dihydropyridines, which inhibit calcium ion flow into cells. This action causes vascular muscle relaxation in cardiac and peripheral blood vessels, reducing blood pressure and increasing blood flow. The group of medications to which manidipine belongs does not generally affect the strength of heart contractions or alter the heart rate. Other uses of calcium channel blockers include the treatment of angina, migraines, and high blood pressure, or pulmonary hypertension.
Other types of calcium channel blockers include the benzothiazepines, such as dilitiazem, and the phenylalkylamines, like verapamil. Each group inhibits calcium ions but does so in different ways. The benzothiazepines and dihydropyridines act on cellular surfaces while phenylalkylamines act by binding to the inner cell membrane. Besides lowering blood pressure, benzothiazepines and phenylalkylamines reduce heart rate and the strength of heart contractions.
Patients with congestive heart failure and bradycardia, or a slow heart rate, might be prescribed amlodipine, as this calcium channel blocker has little effect on the heart. Individuals with tachycardia, or increased heart rate, might use dilitiazem or verapamil, which slow the impulses emitted by the heart's sinoatrial node. Different calcium channel blockers within a particular group might also affect different calcium pathways. Some act on channels that affect the blood vessels that enter the kidneys while others affect only blood vessels found along exit pathways. The calcium channel blocker cilnidipine exhibits unique properties, acting on the calcium channels of nerve cells.
Physicians generally take the action of a medication into consideration before prescribing it for a patients, especially if the patient has more than one medical condition. The side effects of manidipine include headache, skin flushing, and dizziness. Patients might also develop skin rashes, general fatigue, and swelling, or edema, of the feet and ankles. Palpitations and sexual dysfunction are also not uncommon side effects of calcium channel blockers. Patients should not drink grapefruit juice two hours before or four hours after taking calcium channel blockers because the beverage increases the level of medication in the bloodstream.
