Cardiovascular drugs: calcium blocker
Calcium blocker defined
A calcium channel blocker otherwise known as calcium blocker is a class of drugs that inhibits the movement of electrolyte calcium into the cells of the heart and arteries. The entry of calcium into the heart’s cell membranes causes contraction and narrowing of the arteries. Calcium blocker drugs are used in the treatment of coronary heart disease by relieving heart contraction and dilating the arteries to provide enough amounts of oxygen. Unlike other drugs, calcium blocker drugs have distinct effects on the heart and circulatory system, which makes them suitable for varied conditions.
Uses and side effects of calcium blocker drugs
Calcium blockers were first introduced in the U.S. in 1981 while sustainable release of its formulations was made available in 1991. These drugs are used to give relief or treat angina, hypertension, arrhythmias (irregular heartbeat), and migraine prophylaxis. However, calcium blocker drugs have not been proven effective in treating patients with unstable angina since they seem not to reduce risks of heart attack. Other effects of calcium blocker drugs in the cardiovascular area include dilation in heart peripheries, reduced heart rate (negative chronotropy), decreased cardiac contractility (negative inotropy), and reduced cardiac conduction (negative dromotropy).
A calcium blocker is also widely used for the treatment of high blood pressure because of its active properties that effect in lowering blood pressure. Also, a calcium blocker drug is effective for treating abnormal heart rate like atrial fibrillation.
The most common known side effects of calcium blocker drugs that have been reported are constipation, nausea, edema (swelling of legs with fluids), headache, rash, low blood pressure, drowsiness, and dizziness.
Diltiazem or verapamil are types of calcium blocker drugs that have more effect on the heart. Administering them on patients with heart failure and to those who had an attack within the past month must be with care because these drugs positively reduce the heart’s ability to pump blood. On the other hand, nifedipine and nicardipine are known dihydropyridine calcium blocker drugs whose benefiting effects are on blood vessels, with a negligible effect on the heart. Nimodipine has effects in the brain’s blood vessels so it used as a preventive drug for spasms in patients who experienced subarachnoid hemorrhage (bleeding in a certain part of the brain).
The calcium blocker drugs
These are the types of calcium blocker drugs in the market: Diltiazem, Verapamil, Amlodipine, Felodipine, Isradipine, Lacidipine, Lercanidipine, Nicardipine, Nifedipine, Nimodipine, and Nisoldipine.