Part 1 – Part 2 – Part 3 – Part 4
This is Part 4 of our series Hypertension medication and today I am going to talk about a family of drugs known as Calcium Channel Blockers. These type of drugs were designed to alter a mechanism in our body cells in order to get results; unfortunately, any time a function is prevented from occurring in our body, it can lead to trouble.
How calcium channel blockers work
Calcium concentrates inside the muscle cells in small amounts in order to allow the muscle to expand and contract. It enters the cells through channels found in the membrane -the outer part- of the cell, known as calcium channels. When the calcium is inside the cell, it allows muscles to contract, causing the arteries to narrow, which drives blood pressure up.
Calcium channel blocker drugs block these channels so they can not open to allow the calcium enter into the cell. Because the passage of calcium into the cell is an essential factor for the muscles and the heart to contract, when the path is blocked, the cells don‘t get the calcium they need and the muscles don’t contract. This in turn widens the veins and vessels that supply blood to them.
This widening effect reduces blood pressure. These type of drugs are useful in the treatment of hypertension and angina pectoris, a condition related to poor oxygen supply to the heart muscle and characterized by brief attacks of chest pain.
Two types of channel blockers
There are two types of channel blockers:
1. The short-acting drugs that need to be taken several times a day.
2. The long-acting drugs; they are slower to work but they are more effective at lowering blood pressure.
Side effects of calcium channel blockers
These drugs can have some serious effects, especially when taken with other heart medications, diuretics, and anti-seizure medications. Calcium channel blockers can cause low blood pressure, especially in people who are also taking a beta blocker. Studies have shown that people taking the short-acting calcium blockers have a greater chance of having a heart attack than people taking the long-acting kind. Discuss this with your doctor to make sure you are getting the best possible kind.
Other possible side effects of these drugs are loss of potassium. They also interfere with normal carbohydrate metabolism, definitely a problem if you have diabetes. They can cause severe liver damage and fluid accumulation in the hands, legs, and feet, causing them to swollen.
Calcium channel blocker may cause in rare occasions congestive heart failure.
Most common calcium blocker drugs prescribed for hypertension
Generic name Brand name
Diltiazem Anginyl, Cardizem
Nifedipine Adalat, Nifedin
Verapamil Calan, Cordilox, Isoptin, Vasolan
If you are currently taking a drug for high blood pressure, do not suddenly stop taking it on your own, as this could trigger a heart attack, a stroke, or sudden death. Any change in your current medication should be done only in consultation with your physician.