- Heart problems warning: Avoid taking verapamil if you have serious damage to the left side of your heart or moderate to severe heart failure. Also, avoid taking it if you have any degree of heart failure and are receiving a beta blocker drug.
- Dizziness warning: Verapamil may cause your blood pressure to drop below normal levels. This may cause you to feel dizzy.
- Dosage warning: Your doctor will determine the right dose for you and may increase it gradually. Verapamil takes a long time to break down in your body, and you may not see an effect right away. Don’t take more than prescribed. Taking more than the recommended dosage won’t make it work better for you.
Verapamil oral capsule is a prescription medication that’s available as the brand-name drugs Verelan PM (extended-release) and Verelan (delayed-release). The extended-release oral capsule is also available as a generic drug. Generic drugs usually cost less. In some cases, they may not be available in every strength or form as the brand.
Verapamil is also available as an extended-release oral tablet (Calan SR) and an immediate-release oral tablet (Calan). Both forms of these tablets are also available as generic drugs.
Why it's used
Verapamil extended-release forms are used to lower your blood pressure.
How it works
Verapamil is a calcium channel blocker. It works to relax your blood vessels and improve blood flow, which helps to lower blood pressure.
This medication affects the amount of calcium found in your heart and muscle cells. This relaxes your blood vessels, which can reduce the amount of work your heart has to do.
Verapamil oral capsule may make you dizzy or drowsy. Don’t drive, operate heavy machinery, or do anything that requires mental alertness until you know how it affects you. It may also cause other side effects.
Most common side effects
The most common side effects that occur with verapamil include:
- face flushing
- nausea and vomiting
- sexual problems, such as erectile dysfunction
- weakness or tiredness
Serious side effects
If you experience any of these serious side effects, call your doctor right away. If your symptoms are potentially life threatening, or if you think you’re experiencing a medical emergency, call 911.
- difficulty breathing
- dizziness or light headedness
- fast heartbeat, palpitations, irregular heartbeat, or chest pain
- skin rash
- slow heartbeat
- swelling of your legs or ankles
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.
Verapamil oral capsule can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.
To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.
Examples of drugs that can cause interactions with verapamil are listed below.
Combining certain cholesterol drugs with verapamil may cause you to have increased levels of the cholesterol drug in your body. This may lead to side effects, such as serious muscle pain.
Heart rhythm drugs
- Dofetilide. Taking verapamil and dofetilide together may increase the amount of dofetilide in your body by a large amount. This combination may also cause a serious heart condition called torsade de pointes. Don’t take these medications together.
- Disopyramide. Combining this drug with verapamil may impair your left ventricle. Avoid taking disopyramide 48 hours before or 24 hours after you take verapamil.
- Flecainide. Combining verapamil with flecainide may result in additional effects on the contractions and rhythm of your heart.
- Quinidine. In certain patients, combining quinidine with verapamil may result in extremely low blood pressure. Do not use these drugs together.
- Amiodarone. Combining amiodarone with verapamil may change the way your heart contracts. This may result in slow heart rate, heart rhythm problems, or reduced blood flow. You’ll need to be monitored very closely if you’re on this combination.
- Digoxin. Long-term use of verapamil can increase the amount of digoxin in your body to toxic levels. If you take any form of digoxin, your digoxin dose may need to be lowered, and you’ll need to be monitored very closely.
- Beta-blockers. Combining verapamil with beta-blockers, such as metoprolol or propranolol, may cause negative effects on heart rate, heart rhythm, and the contractions of your heart. Your doctor will monitor you closely if they prescribe verapamil with a beta-blocker.
Heart failure drug
Taking verapamil and ivabradine together can increase the amount of ivabradine in your body. This raises your risk of serious heart rhythm problems. Do not take these drugs together.
Don’t take eletriptan with verapamil. Verapamil can increase the amount of eletriptan in your body to 3 times as much. This can lead to toxic effects. Don’t take eletriptan for at least 72 hours after you take verapamil.
Verapamil can decrease your heart’s ability to work during general anesthesia. Doses of verapamil and general anesthetics will both need to be adjusted very carefully if they’re used together.
Blood pressure-lowering drugs
- angiotensin-converting enzyme (ACE) inhibitors such as captopril or lisinopril
- diuretics (water pills)
- beta-blockers such as metoprolol or propranolol
Combining blood pressure-lowering drugs with verapamil can lower your blood pressure to a dangerous level. If your doctor prescribes these drugs with verapamil, they will monitor your blood pressure closely.
Verapamil may increase or decrease the levels of the following drugs in your body:
Your doctor will monitor your levels of these drugs if you are also given verapamil. The following drugs may decrease the levels of verapamil in your body:
Your doctor will monitor you closely if you receive these drugs in combination with verapamil.
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.
Verapamil oral capsule comes with several warnings.
Verapamil can cause a severe allergic reaction. Symptoms may include:
- trouble breathing
- swelling of your throat or tongue
- rash or itching
- swollen or peeling skin
- chest tightness
- swelling of your mouth, face, or lips
Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal.
Grapefruit juice: Grapefruit juice may increase the amount of verapamil in your body. This may lead to increased side effects. Avoid drinking grapefruit juice while taking verapamil.
Verapamil may increase the amount of alcohol in your blood and make alcohol effects continue longer. Alcohol may also make the effects of verapamil stronger. This can cause your blood pressure to be too low.
Warnings for people with certain health conditions
For people with heart problems: This includes serious left ventricle dysfunction and heart failure. Avoid taking verapamil if you have serious damage to the left side of your heart or moderate to severe heart failure. Also, avoid taking it if you have any degree of heart failure and are receiving a beta blocker drug.
For people with low blood pressure: Don’t take verapamil if you have low blood pressure (systolic pressure less than 90mm Hg). Verapamil may decrease your blood pressure too much, which may lead to dizziness.
For people with heart rhythm disturbances: These include sick sinus syndrome, ventricular arrhythmias, Wolff-Parkinson-White syndrome, 2nd or 3rd degree atrioventricular (AV) block, or Lown-Ganong-Levine syndrome. If you have any of these conditions, verapamil may cause ventricular fibrillation or atrioventricular block.
For people with kidney or liver disease: Liver and kidney disease may affect how well your body processes and clears this drug. Having reduced kidney or liver function may cause the drug to build up, which can increase side effects. Your dose may need to be adjusted.
Warnings for other groups
For pregnant women: Verapamil is a category C pregnancy drug. That means two things:
- Research in animals has shown adverse effects to the fetus when the mother takes the drug.
- There haven’t been enough studies done in humans to be certain how the drug might affect the unborn baby.
Using verapamil during pregnancy may cause negative effects in the fetus such as low heart rate, low blood pressure, and abnormal heart rhythm. Tell your doctor if you’re pregnant or plan to become pregnant. Verapamil should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
For women who are breastfeeding: Verapamil passes through breast milk. It may cause negative effects in a breastfeeding baby. Talk with your doctor before breastfeeding while taking this medication.
For children: The safety and effectiveness of verapamil haven’t been established in people younger than 18 years old.
This dosage information is for verapamil oral capsules and oral tablets. All possible dosages and forms may not be included here. Your dose, form, and how often you take it will depend on:
- your age
- the condition being treated
- how severe your condition is
- other medical conditions you have
- how you react to the first dose
Forms and strengths
- Form: oral extended-release tablet
- Strengths: 120 mg, 180 mg, 240 mg
- Form: oral extended-release capsule
- Strengths: 100 mg, 120 mg, 180 mg, 200 mg, 240 mg, 300 mg
- Form: oral immediate-release tablet
- Strengths: 40 mg, 80 mg, 120 mg
- Form: oral extended-release capsule
- Strengths: 120 mg, 180 mg, 240 mg, 360 mg
Brand: Verelan PM
- Form: oral extended-release capsule
- Strengths: 100 mg, 200 mg, 300mg
- Form: oral immediate-release tablet
- Strengths: 80 mg, 120 mg
Brand: Calan SR
- Form: oral extended-release tablet
- Strengths: 120 mg, 240 mg
Dosage for high blood pressure
Adult dosage (ages 18 years and older)
Immediate-release tablet (Calan):
- The starting dose is 80 mg taken three times per day (240 mg/day).
- If you don’t have a good response to 240 mg/day, your doctor may increase your dose to 360–480 mg/day. However, doses higher than 360 mg/day generally do not provide added benefit.
Extended-release tablet (Calan SR):
- The starting dose is 180 mg taken every morning.
- If you don’t have good response to 180 mg, your doctor may increase your dose slowly as follows:
- 240 mg taken every morning
- 180 mg taken every morning and 180 mg taken every evening or 240 mg taken every morning plus 120 mg taken every evening
- 240 mg taken every 12 hours
Extended-release capsule (Verelan):
- The starting dose is 120 mg taken once per day in the morning.
- The maintenance dose is 240 mg taken once per day in the morning.
- If you don’t have good response to 120 mg, your dose may be increased to 180 mg, 240 mg, 360 mg, or 480 mg.
Extended-release capsule (Verelan PM):
- The starting dose is 200 mg taken once per day at bedtime.
- If you don’t have good response to 200 mg, your dose may be increased to 300 mg or 400 mg (two 200 mg capsules)
Senior dosage (ages 65 years and older)
Your doctor may start with a lower dose and increase your dose slowly if you’re over the age of 65.
If you have a neuromuscular condition such as Duchenne muscular dystrophy or myasthenia gravis, your doctor may decrease your dose of verapamil.
Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always to speak with your doctor or pharmacist about dosages that are right for you.
Take as directed
Verapamil oral capsule is used for long-term treatment. It comes with risks if you don’t take it as prescribed.
If you don’t take it at all: If you don’t take verapamil at all, you risk increased blood pressure. This may lead to hospitalization and death.
If you take too much: You may experience dangerously low blood pressure, slowed heart rate, or slowed digestion. If you think you’ve taken too much, go to your nearest emergency room, or call a poison control center. You may need to stay for at least 48 hours in a hospital for observation and care.
What to do if you miss a dose: If you miss a dose, take it as soon as you can. However, if it’s just a few hours until your next dose, wait and take only the next dose. Never try to catch up by taking two doses at once. This could result in toxic side effects.
How to tell if the drug is working: You may experience dangerously low blood pressure, slowed heart rate, or slowed digestion. If you think you’ve taken too much, go to your nearest emergency room, or call a poison control center. You may need to stay for at least 48 hours in a hospital for observation and care.
Keep these considerations in mind if your doctor prescribes verapamil oral capsules for you.
- You can take the extended-release capsule with or without food. (The drug maker does not indicate whether you should take the immediate-release tablet with or without food.)
- You can cut the extended-release tablet, but don’t crush it. If you need to, you can cut the tablet in half. Swallow the two pieces whole.
- Don’t cut, crush, or break apart the extended-release capsules. However, if you’re taking Verelan or Verelan PM, you can open the capsule and sprinkle the contents onto applesauce. Swallow this immediately without chewing and drink a glass of cool water to make sure all of the contents of the capsule are swallowed. The applesauce shouldn’t be hot.
Store in temperatures from 59–77°F (15–25°C).
Protect the medication from light.
A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.
When traveling with your medication:
- Always carry it with you or in your carry-on bag.
- Don’t worry about airport X-ray machines. They can’t hurt this medication.
- You may need to show your pharmacy’s preprinted label to identify the medication. Keep the original prescription-labeled box with you when traveling.
To see how well this medication is working, your doctor will monitor your heart activity and blood pressure. They may use an electrocardiogram (ECG) to monitor your heart activity. Your doctor may instruct you on how to monitor your heart rate and blood pressure at home with an appropriate monitoring device. Your doctor may also periodically test your liver function with a blood test.
There are other drugs available to treat your condition. Some may be more suitable for you than others. Talk to your doctor about possible alternatives.
Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.