Calcium channel blockers: Uses, common brands, and safety info

If you or a loved one has high blood pressure or a heart condition, you may have heard of medications like diuretics, beta blockers, ACE inhibitors, ARBs (angiotensin II receptor blockers), and calcium channel blockers.

Calcium channel blockers (also known as CCBs for short) are a class of antihypertensive medications used to treat various conditions, such as high blood pressure. In fact, a CCB called amlodipine is among the most popular drugs prescribed by city and state. Amlodipine was also the third most popular drug among SingleCare users in 2020.

Continue reading to learn more about CCBs, including what they are used for, side effects, and safety information.

Other calcium channel blockers

In addition to oral calcium channel blockers, there are injectable calcium channel blockers. These include Cleviprex (clevidipine), as well as diltiazem, verapamil, and nicardipine.

What are calcium channel blockers?

Calcium channel blockers (CCBs) are also called calcium antagonists. They block calcium from moving into the heart and blood vessel muscle cells, and by doing so, help the muscles relax. CCBs can be used to treat various conditions, including high blood pressure, abnormal heart rhythm, and chest pain. CCBs are usually prescribed by an internal medicine physician or cardiologist (doctor of cardiology).

How do calcium channel blockers work?

Calcium channel blockers bind to L-type calcium channels and prevent calcium from getting into the smooth muscle cells of the heart and arteries. Calcium causes stronger and more forceful contractions. So, by decreasing the amount of calcium, the heart does not contract as forcefully. CCBs relax and widen blood vessels, lower heart rate, and lower blood pressure.

What are calcium channel blockers used for?

While indications vary by product, CCBs may be used alone or in combination with other medications—such as cholesterol drugs or other blood pressure medications. A cardiologist may prescribe CCBs for:

• Hypertension (high blood pressure)

• Coronary spasm

• Angina pectoris (chest pain) associated with coronary artery disease (heart disease or cardiovascular disease)

• Arrhythmia (irregular heartbeat)

• Supraventricular dysrhythmias (abnormally fast heartbeat)

• Hypertrophic cardiomyopathy (abnormally thick heart muscle)

• Pulmonary hypertension (high blood pressure that affects the lungs)

• Raynaud’s phenomenon (decreased blood flow to extremities, causing numbness)

• Subarachnoid hemorrhage (bleeding between the brain and tissue that covers the brain)

• Migraine prevention

Types of calcium channel blockers

Calcium channel blockers can be classified as dihydropyridines and nondihydropyridines. CCBs are available in both short-acting and long-acting forms.

Dihydropyridines

These CCBs bind to calcium channels in vascular smooth muscle, causing vasodilation and lower blood pressure. Examples of dihydropyridines are amlodipine, nifedipine, and felodipine. 

Nondihydropyridines

These CCBs bind to calcium channels in the sinoatrial and atrioventricular node and affect the heart muscle and blood vessels. Examples of nondihydropyridines include verapamil and diltiazem. 

Who can take calcium channel blockers?

Men and women can generally take CCBs unless they fall into one of the contraindicated groups listed below. Your doctor can review your medical conditions, history, and medications that you take to ensure that a CCB is safe for you. 

Women who are pregnant, planning to become pregnant or breastfeeding should consult a healthcare provider for professional medical advice regarding CCB use.

Amlodipine can be used in children ages 6 years and older for hypertension. Nifedipine, verapamil, and diltiazem, on the other hand, have not been studied in children.

Generally, older adults can take CCBs. However, because of the possibility of decreased kidney, liver, or cardiovascular function, as well as the possibility of drug interactions (depending on the individual), dosing should start on the lower end, increasing slowly as tolerated if needed, and as directed by the physician.

Are calcium channel blockers safe?

Recalls

Amlodipine has been recalled as part of combination products (drugs that contain amlodipine plus another medication in one pill), but not as a single drug product.

Restrictions

All CCBs are contraindicated (should not be used) in people with:

• Allergies to the drugs or ingredients

• Sick sinus syndrome (except in patients with an artificial pacemaker)

• Severely low blood pressure

• Acute myocardial infarction (heart attack)

• Lung congestion

RELATED: Cardiac arrest vs. heart attack: Is there a difference?

Due to the possibility of causing slowed heartbeat and worsening cardiac output, nondihydropyridine CCBs are contraindicated in people with:

• Heart failure with reduced ejection fraction (left ventricle muscle is not pumping as well as normal)

• Second or third-degree AV blockade

• Sick sinus syndrome

Other cautions:

• CCBs may cause AV blockade or sinus bradycardia, especially if taken with other drugs that can slow cardiac conduction.

• Low blood pressure with or without fainting may occur.

• Swelling (edema) of the arms and legs may occur.

• Use with caution in people with liver or kidney problems.

• Do not chew or crush extended-release formulations—the drug names usually end in CD, XR, XL, or XT and are meant to release over time. Ask your pharmacist if you are unsure if your prescription is immediate-release or extended-release.

• Tell your doctor about all of your medical conditions so he or she can ensure a CCB is safe for you. 

• CCBs can interact with other medications. Tell your doctor about all of the medications you take, including prescription medicines, over-the-counter drugs, and vitamins. 

• Do not smoke or drink alcohol while taking a CCB.

• Grapefruit juice interacts with some CCBs. Ask your healthcare provider if you can consume grapefruit products with your CCB.

Can you take calcium channel blockers while pregnant or breastfeeding?

Certain CCBs may be used during pregnancy, as determined on a case-by-case basis and under the doctor’s close supervision. Because there is little data on CCBs and pregnancy, generally, CCBs should only be used during pregnancy if clearly needed and if benefits outweigh the risks. 

CCB use while breastfeeding may be safe but check with your doctor to make sure it is safe for you based on your unique medical conditions and history.

Ask your doctor before using a CCB if you are pregnant, planning to become pregnant, or breastfeeding. 

Are calcium channel blockers controlled substances?

No, calcium channel blockers are not controlled substances.

Common calcium channel blocker side effects

Common side effects of calcium channel blockers include: 

• Tiredness 

• Flushing

• Swelling of the abdomen, ankles, feet

• Heartburn, stomach pain, nausea 

• Arrhythmia (irregular heartbeat) or palpitations (fast heartbeat)

• Constipation

• Dizziness 

Other side effects that are less common include fast (tachycardia) or slow (bradycardia) heartbeat, wheezing, cough, shortness of breath, difficulty swallowing, and numbness or tingling in the hands or feet.

Side effects that are rare include headache, fainting, jaundice, fever, rash, vivid dreams, and swollen gums. 

In rare cases, a heart attack may occur or chest pain may worsen when starting a CCB. If this happens, get emergency medical help.

Serious allergic reactions are rare. If you have symptoms of an allergic reaction, such as hives, difficulty breathing, or swelling of the face, lips, or tongue, seek emergency medical treatment. 

Other side effects may occur. Consult your healthcare professional for a full list of side effects associated with CCBs. 

How much do calcium channel blockers cost?

The price of calcium channel blockers varies by product, dosage, and quantity. CCBs range from $55 to $950 without insurance and before discounts. However, many CCBs are available in affordable generic versions that cost less than $10 per month with insurance or with a prescription discount card. In fact, using a free SingleCare coupon can save you up to 80% on your prescriptions. Ask your pharmacist to help you compare prices on your medications.