Calcium Channel Blockers

Calcium channel blockers (CCBs) are a class of medications used to treat high blood pressure. They’re also called calcium antagonists, and are as effective as ACE (angiotensin-converting-enzyme) inhibitors in reducing blood pressure. How long-lasting they are, how they’re eliminated from the body, and how they affect heart rate differentiates one CCB from another.

Who Should Take Calcium Channel Blockers

People who have hypertension (high blood pressure), heart arrhythmia (irregular heartbeats), or angina-related chest pain may be prescribed CCBs as a treatment option. High blood pressure can also be treated with other forms of medication. You could be directed to take both a CCB and another hypertensive drug at the same time.

How They Work

CCBs reduce blood pressure by limiting the amount of calcium or the rate at which calcium flows into the heart muscle and arterial cell walls. Calcium stimulates the heart to contract more forcefully. When calcium flow is limited, your heart’s contractions aren’t as strong and your blood vessels are able to relax, leading to lower blood pressure.

Calcium channel blocking medicines are available in a number of oral formats, ranging from short-acting dissolving tablets to extended-release capsules. Dosage varies according to your overall health and medical history. Your medical care provider will also take your age into consideration before prescribing a blood pressure-lowering medication. CCBs are most effective and less likely to cause side effects in patients over the age of sixty-five. Three classes of CCB drugs exist. They are:

  • L-type
  • dihydropyridines
  • non-dihydropyridines

Dihydropyridines are more commonly used to treat hypertension than L-type or non-dihydropyridine drugs. This is due to their ability to reduce arterial pressure and vascular resistance. Dihydropyridine calcium antagonists usually end in the suffix “-pine” and include:

  • amlodipine
  • felodipine
  • isradipine
  • nicardipine
  • nifedipine
  • nimodipine
  • nitrendipine

Other commonly prescribed CCBs used to treat angina and a rapid heartbeat are verapami, bepridil, and diltiazem.

ACE inhibitors, diuretics, and beta blockers also lower blood pressure. According to the Mayo Clinic, these drugs are generally more effective for most people with hypertension than CCBs are. However, African-Americans may benefit more from CCBs as a first line of treatment for high blood pressure.

Side Effects and Risks

CCBs may interact with other drugs or supplements you take, so be sure that your doctor has an updated list of all of your medications, vitamins, and herbal supplements. CCB drugs and grapefruit products (including whole fruit and juice) shouldn’t be taken together, explains the Texas Heart Institute. Grapefruit products interfere with the normal excretion of the medication. It could be potentially dangerous if large amounts of the drug accumulate in your body.

Wait at least four hours after you have taken your medication before drinking grapefruit juice or eating grapefruit. Refrain from smoking when taking CCBs, as a rapid heartbeat can result. Other side effects of CCB medications include:

  • dizziness
  • headache
  • constipation
  • heartburn
  • nausea
  • skin rash or flushing (redness of the face)
  • edema (swelling) in the lower extremities
  • fatigue

CCBs also can cause low blood glucose in some people, particularly those whose dosage is higher than 60mg daily. Alert your physician to any side effects that you experience. Your doctor may adjust your dosage or switch you to another medication if side effects are prolonged, uncomfortable, or pose a threat to your health.

Natural Calcium Channel Blockers

Magnesium is an example of a nutrient that acts as a natural CCB, as detailed in studies published in a 1984 issue of the American Heart Journal. Magnesium is an electrolyte, which is a mineral that holds an electrical charge in the body and helps regulate fluid levels. Magnesium is essential for protein and antioxidant synthesis and can be beneficial to cardiac health and the regulation of blood pressure levels. Consult your doctor to determine if the consumption of foods high in magnesium will affect the potency of your medication if you’re taking CCB medications. Magnesium-rich foods include:

  • brown rice
  • almonds, peanuts, and hazelnuts
  • oat bran
  • shredded wheat cereal
  • bananas
  • spinach
  • okra
  • blackstrap molasses