- What is verapamil, and how does it work (mechanism of action)?
- What brand names are available for verapamil?
- Is verapamil available as a generic drug?
- Do I need a prescription for verapamil?
- What are the side effects of verapamil?
- What is the dosage for verapamil?
- Which drugs or supplements interact with verapamil?
- Is verapamil safe to take if I'm pregnant or breastfeeding?
- What else should I know about verapamil?
What is verapamil, and how does it work (mechanism of action)?
Verapamil belongs to a class of medications called calcium channel blockers (CCBs), which includes amlodipine (Norvasc), diltiazem (Cardizem, Dilacor), nifedipine (Adalat, Procardia) as well as others. These medications block the movement of calcium into the muscle cells of the coronary arteries (the arteries supplying the heart with blood) as well as the other arteries of the body. Since calcium triggers contraction of muscles, blocking entry of calcium relaxes the muscles that surround the arteries. This relaxation allows arteries to become larger so that more blood can flow through them. Thus, verapamil is useful in treating and preventing chest pain (angina) resulting from spasm (contraction) of the coronary arteries that reduces the flow of blood to the heart. Relaxing muscles in the arteries of the rest of the body lowers blood pressure and thereby reduces the pressure against which the heart must pump blood. As a result, the heart works less and requires less oxygen-carrying blood. This allows the heart to work with the reduced flow of blood caused by coronary artery disease and prevents angina (which occurs whenever the flow of blood to the heart is inadequate). Verapamil also decreases the conduction of electrical impulses through the heart that control the coordination of contraction. As a result, the rate of contraction slows. Verapamil was approved by the FDA in March 1982.
What are the side effects of verapamil?
Common side effects of Verapamil are
Other side effects include
Verapamil also can cause mildly abnormal liver tests that usually return to normal with discontinuation of the medication. Verapamil may reduce heart rate. Verapamil also can cause excessive lowering of blood pressure in rare instances. Verapamil can aggravate heart failure, especially in patients with poor function of their heart muscle.
What is the dosage for verapamil?
Verapamil can be taken with food.
- Angina (immediate release formulations): 80-160 mg three times daily. Angina (extended release formulations): 180-540 mg at bedtime.
- Hypertension (immediate release): 80-320 mg twice daily. Hypertension (extended release): 120-480 mg once or twice daily depending on the brand.
- Migraine: 160-320 mg three to four times daily.
Which drugs or supplements interact with verapamil?
Concurrent use of verapamil with a beta blocker (another class of medications that slow heart rate) can cause profound and dangerous reductions in heart rate. Verapamil can raise the levels of some drugs in blood including digoxin (Lanoxin), theophylline (Slo-Bid), cyclosporin, and carbamazepine (Tegretol). Therefore, monitoring of the levels of these drugs is important to avoid toxicity.
Verapamil may reduce blood levels of lithium (Eskalith, Lithobid) in some patients. For unclear reasons some patients who took both verapamil and lithium have noticed increased side effects of lithium without increases in their blood levels of lithium.
The use of "statins" (for example, simvastatin or lovastain) in combination with verapamil has been associated with reports of myopathy/rhabdomyolysis because verapamil reduces the break down of these statins in the liver. The dose of simvastatin in patients on verapamil should not exceed 10 mg daily and the dose of lovastatin (Mevacor, Altoprev) should not exceed 40 mg daily. Lower starting and maintenance doses of other statins (for example, atorvastatin [Liptor]) may be required since verapamil also may increase the plasma concentration of these drugs also. Rifampin and phenobarbital increase the elimination of verapamil, potentially reducing the effect of verapamil.
Is verapamil safe to take if I'm pregnant or breastfeeding?
Safety of verapamil during pregnancy has not been established. Verapamil crosses the placenta and enters the fetus.
Safety in nursing mothers has not been established. Verapamil is excreted in human milk.
What else should I know about verapamil?
What preparations of verapamil are available?
Immediate release tablets: 40, 80, and 120 mg; sustained release caplets: 120, 180, 240,and 360 mg; extended release tablets: 100, 120, 180, 200, 240, and 300 mg; Injection: 2.5 mg/mL
How should I keep verapamil stored?
Verapamil should be stored at room temperature 15 C - 30 C (59 F - 86 F) in a tight, light- resistant container.
Latest Cholesterol News
Verapamil (Calan, Verelan, Verelan PM, [DISCONTINUED: Isoptin, Isoptin SR, Covera-HS]) is a medication prescribed for the prevention and treatment of the heart pain of angina, high blood pressure, and abnormally fast heart rhythms such as atrial fibrillation. Although verapamil is not an approved indication for migraine, it is used for preventing migraine headaches.
Multimedia: Slideshows, Images & Quizzes
Atrial Fibrillation (A-Fib) Quiz: Test Your Medical IQ
Learn the causes, symptoms, and treatments of the common heart abnormality known as atrial fibrillation (A-fib)....
Picture of Hypertension
High blood pressure, defined as a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140...
Heart Disease: Symptoms, Signs, and Causes
What is heart disease (coronary artery disease)? Learn about the causes of heart disease. Symptoms of heart disease include chest...
Heart Disease: Causes of a Heart Attack
Learn about heart disease and heart attack symptoms and signs of a heart attack in men and women. Read about heart disease...
Related Disease Conditions
Angina (Symptoms, Causes, Types, Diagnosis, and Treatment)
Angina is chest pain due to inadequate blood supply to the heart. Angina symptoms may include chest tightness, burning,...
Atrial Fibrillation (AFib) Symptoms, ECG, and Treatment Medications
Atrial fibrillation (AF or AFib) is an abnormality in the heart rhythm which involves irregular and often rapid beating of the...
High Blood Pressure (Hypertension) Signs, Causes, Diet, and Treatment
High blood pressure (hypertension) is a disease in which pressure within the arteries of the body is elevated. About 75 million...
Migraine headache is a type of headache associated with a sensitivity to light, smells, or sounds, eye pain, severe pounding on...
Mitral Valve Prolapse (Syndrome, Symptoms, Causes, Treatment, Surgery)
Mitral valve prolapse (MVP), also called "click murmur syndrome" and "Barlow's syndrome," is the most common type of heart valve...
Palpitations (Causes and Symptoms)
Palpitations are uncomfortable sensations of the heart beating hard, rapidly, or irregularly. Some types of palpitations are...
Fainting (Syncope) Symptoms, Causes, Treatment, and Prevention
Fainting, also referred to as blacking out, syncope, or temporary loss of consciousness has many causes. Often a person will have...
Esophageal achalasia is a disease of the esophagus that mainly affects young adults. Achalasia makes it difficult to swallow, can...
Headaches can be divided into two categories: primary headaches and secondary headaches. Migraine headaches, tension headaches,...
Peyronie's Disease (Curvature of the Penis)
Peyronie's disease or curvature of the penis (Peyronie disease) is a condition in which scar tissue develops inside the penis....
Cluster headaches are a type of headache that recurs over a period. Episodes can last one to three times a day during this time,...
High Blood Pressure Treatment (Natural Home Remedies, Diet, Medications)
High blood pressure (hypertension) means high pressure (tension) in the arteries. Treatment for high blood pressure include...
Heart disease (coronary artery disease) occurs when plaque builds up in the coronary arteries, the vessels that supply blood to...
Febrile seizures, or convulsions caused by fever, can be frightening in small children or infants. However, in general, febrile...
Atrial Flutter (Symptoms, Causes, ECG, and Treatments)
Atrial flutter is a problem with the atria of the heart. In atrial flutter the atria of the heart rapidly and repeatedly beat...
Treatment & Diagnosis
- Atrial Fibrillation A-Fib FAQs
- Medication Disposal
- Dangers of Mixing Medications
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Drugs: Buying Prescription Drugs Online Safely
- Drugs: The Most Common Medication Errors
- Grapefruit Juice and Drug Interactions
- Generic Drugs, Are They as Good as Brand-Names?
Medications & Supplements
- nicardipine, Cardene, Cardene SR
- diltiazem (Cardizem, Cardizem CD, Cardizem LA, Tiazac, Cartia XT, Diltzac, Dilt-CD, and several oth)
- amlodipine (Norvasc)
- nifedipine (Procardia, Adalat, Afeditab)
- bepridil (Vascor, Bepadin - Discontinued)
- Drugs: Questions to Ask Your Doctor or Pharmacist about Your Drugs
- Calcium Channel Blockers (CCBs)
- Drug Interactions
- High Blood Pressure Drugs (Hypertension)
Prevention & Wellness
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.