What Are Dihydropyridine Calcium Channel Blockers?

Dihydropyridine calcium channel blockers are a class of drugs used mainly to treat hypertension, or high blood pressure and angina. There are a number of different drugs included in the class, such as amlodipine, nifedipine, felodipine and nicardipine, each which may be known by different trade names in different countries, according to manufacturer. In most countries the dihydropyridine calcium channel blockers are available by prescription only and treatment and response will be monitored by the prescribing doctor.

The way in which dihydropyridine calcium channel blockers work, also known as their mechanism of action, is by blocking the calcium channels in the blood vessels. Calcium is used by the muscles to contract, so by blocking the channels the dihydropyridine calcium channel blockers essentially decrease the contraction of the muscles in the blood vessels which widens them, lowering blood pressure and decreasing the work load of the heart. The different types of calcium channel blockers (CCBs) within the class have slightly different potencies and will be chosen on a patient-by-patient basis accordingly.

Hypertension, or high blood pressure, is one of the most common clinical conditions worldwide and, if left untreated, can result in serious conditions such as heart attack or stroke. There are a number of causes of hypertension, but high blood pressure is commonly seen with increasing age. Diagnosis is done simply by measurement of the blood pressure, a non-invasive procedure that should be performed annually, as hypertension often has no symptoms and can go unnoticed.

Depending on the severity of the hypertension and the cause thereof the doctor will choose the most suitable treatment, taking numerous factors into consideration including other clinical conditions. In mild cases, non-drug measures, such as changing the lifestyle to include exercise, weight loss and a healthy diet may be sufficient. Where this is insufficient, drug treatment may be started. There are a number of different classes of drugs used to treat hypertension, including dihydropyridine calcium channel blockers, with each acting by a slightly different mechanism.

As with any medication, dihydropyridine calcium channel blockers may interact with other drugs, including homeopathic, complementary and over-the-counter preparations. They may also have adverse effects and be contraindicated in people with some underlying conditions. These should be discussed with the treating doctor, as should pregnancy, planned pregnancy and lactation. Adverse effects which have been reported include headache, dizziness and light-headedness, especially upon standing up. Any side effects experienced should be discussed with the prescribing doctor.