- 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.
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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.
Reference: FDA Prescribing Information
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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.
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Angina (Symptoms, Causes, Types, Diagnosis, and Treatment)
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Atrial Fibrillation (AF, AFib)
Atrial fibrillation (AF or AFib) is an abnormality in the heart rhythm which involves irregular and often rapid beating of the...
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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...
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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....
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Treatment & Diagnosis
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Medications & Supplements
- nicardipine, Cardene, Cardene SR
- diltiazem (Cardizem, Cardizem CD, Cardizem LA, Tiazac, Cartia XT, Diltzac, Dilt-CD, and several oth)
- amlodipine, Norvasc
- nifedipine, Adalat (discontinued brand), Procardia, Afeditab, Nifediac
- bepridil (Vascor, Bepadin - Discontinued)
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- Calcium Channel Blockers (CCBs)
- Drug Interactions
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AchalasiaEsophageal achalasia is a disease of the esophagus that mainly affects young adults. Achalasia makes it difficult to swallow, can cause chest pain, and may lead to regurgitation. Here we discuss achalasia symptoms, surgery, treatment, and causes. Learn the definition of achalasia and what you can do to treat the disease.
Angina SymptomsAngina is chest pain due to inadequate blood supply to the heart. Angina symptoms may include chest tightness, burning, squeezing, and aching. Coronary artery disease is the main cause of angina but there are other causes. Angina is diagnosed by taking the patient's medical history and performing tests such as an electrocardiogram (EKG), blood test, stress test, echocardiogram, cardiac CT scan, and heart catheterization. Treatment of angina usually includes lifestyle modification, medication, and sometimes, surgery. The risk of angina can be reduced by following a heart healthy lifestyle.
Atrial fibrillation (AF or AFib) is an abnormality in the heart rhythm which involves irregular and often rapid beating of the heart. Symptoms may include:
- Shortness of breath
- Chest pain
Treatment may include medication or procedures like cardioversion or ablation to normalize the heart rate.
Atrial Fibrillation QuizLearn the causes, symptoms, and treatments of the common heart abnormality known as atrial fibrillation (A-fib).
FaintingFainting, also referred to as blacking out, syncope, or temporary loss of consciousness has many causes. Often a person will have signs or symptoms prior to the fainting episode. Diagnosis and treatment depends upon the cause of the fainting or syncope episode.
HeadacheHeadaches can be divided into two categories: primary headaches and secondary headaches. Migraine headaches, tension headaches, and cluster headaches are considered primary headaches. Secondary headaches are caused by disease. Headache symptoms vary with the headache type. Over-the-counter pain relievers provide short-term relief for most headaches.
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High Blood Pressure Hypertension
High blood pressure (hypertension) is a disease in which pressure within the arteries of the body is elevated. About 75 million people in the US have hypertension (1 in 3 adults), and only half of them are able to manage it. Many people do not know that they have high blood pressure because it often has no has no warning signs or symptoms.
Systolic and diastolic are the two readings in which blood pressure is measured. The American College of Cardiology released new guidelines for high blood pressure in 2017. The guidelines now state that blood normal blood pressure is 120/80 mmHg. If either one of those numbers is higher, you have high blood pressure.
The American Academy of Cardiology defines high blood pressure slightly differently. The AAC considers 130/80 mm Hg. or greater (either number) stage 1 hypertension. Stage 2 hypertension is considered 140/90 mm Hg. or greater.
If you have high blood pressure you are at risk of developing life threatening diseases like stroke and heart attack.
REFERENCE: CDC. High Blood Pressure. Updated: Nov 13, 2017.
Hypertension PictureHigh blood pressure, defined as a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90. See a picture of Hypertension and learn more about the health topic.
Migraine headaches are severe headaches that are sensitive to light, sounds, and smells. Some people who suffer from migraines also have severe head pain. People also have symptoms of nausea and vomiting. Common migraine triggers may include:
- Certain foods
- Changes in barometric pressure
- Other phenomenon
They are diagnosed by a doctor if the headache pattern fits established migraine headache criteria. Over-the-counter (OTC) and prescription medications are sometime used to treat acute migraines. To prevent or reduce the frequency and severity of them doctors recommend supplements and prescription medications, for example:
- Blood pressure drugs
- Anti-seizure drugs
Lifestyle modification helps in migraine management. Many people who suffer from migraines get relief from their condition by keeping a headache diary, identifying and avoiding triggers, and taking appropriate medication.
Mitral Valve ProlapseMitral valve prolapse (MVP) is also also known as "click murmur syndrome" and "Barlow's syndrome." Mitral valve prolapse is the most common heart valve abnormality. Signs and symptoms of mitral valve prolapse include: fatigue, palpitations, chest pain, anxiety, and migraine headaches. Echocardiography is the most useful test for mitral valve prolapse. Most patients do not need any treatment, however, patients with severe prolapse may need treatment.
ParathyroidectomyParathyroidectomy is the removal of one or more of the parathyroid glands to treat hyperparathyroidism. Risks of parathyroidectomy include:
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- difficulty swallowing thin liquids,
- difficulty breathing,
- and drug reactions.
- damage to the recurrent laryngeal nerve,
- bleeding or hematoma,
- problems maintaining calcium levels in the blood,
- need for further and more aggressive surgery,
- need for a limited or total thyroidectomy,
- prolonged pain,
- impaired healing,
- and recurrence of the tumor.
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. This scar tissue causes the penis to develop an abnormal curvature in the scarred area. At this time, there is no known cause of Peyronie's disease. Symptoms of Peyronie's disease include:
- pain during intercourse or ejaculation,
- the inability to have sexual intercourse,
- an indentation of the shaft at the site where there is plaque or scarring, and
- an angulation of the penis when erect or flaccid.