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Calan SR (Oral)

Generic name: verapamil [ ver-AP-a-mil ]
Brand names: Calan, Calan SR, Covera-HS, Isoptin SR, Verelan, Verelan PM
Drug classes: Calcium channel blockers, Group IV antiarrhythmics

Medically reviewed by Drugs.com. Last updated on Sep 19, 2024.

Uses for Calan SR

Verapamil is used alone or together with other medicines to treat heart rhythm problems, severe chest pain (angina), or high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled .

Verapamil is a calcium channel blocker. It works by affecting the movement of calcium into the cells of the heart and blood vessels. As a result, verapamil relaxes blood vessels and increases the supply of blood and oxygen to the heart while reducing its workload .

This medicine is available only with your doctor's prescription .

Before using Calan SR

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of verapamil in the pediatric population. Safety and efficacy have not been established .

Geriatric

Appropriate studies performed to date have not demonstrated geriatrics-specific problems that would limit the usefulness of verapamil in the elderly. However, elderly patients are more likely to have age-related heart, liver, or kidney problems which may require an adjustment of dose in patients receiving verapamil .

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.

Using this medicine with any of the following may cause an increased risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

Proper use of Calan SR

In addition to the use of this medicine, treatment for your high blood pressure may include weight control and changes in the types of foods you eat, especially foods high in sodium. Your doctor will tell you which of these are most important for you. You should check with your doctor before changing your diet .

Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well .

Remember that this medicine will not cure your high blood pressure, but it does help control it. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease .

Swallow the extended-release tablet whole with a full glass of water. Do not break, crush, or chew it. It is best to take this medicine with food .

If you cannot swallow the verapamil extended-release capsules, you may open it and sprinkle the pellets contained in the capsule on one tablespoon of applesauce. This mixture must be swallowed immediately with a glass of cool water. The applesauce should not be hot and should be soft enough to be swallowed without chewing. Do not chew or crush the pellets .

If you are taking the extended-release tablets, you may sometimes notice what looks like a tablet in your stool. This is the empty tablet shell that is left after the medicine has been absorbed .

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Detailed Calan SR dosage information

Precautions while using Calan SR

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly and to check for unwanted effects .

Low blood pressure (hypotension) may occur while taking this medicine. Check with your doctor right away if you have the following symptoms: blurred vision; confusion; severe dizziness, faintness, or lightheadedness when getting up from a lying or sitting position suddenly; sweating; or unusual tiredness or weakness .

While you are taking this medicine be careful to limit the amount of alcohol that you drink. Alcohol increases dizziness and drowsiness and also lowers blood pressure .

Side Effects of Calan SR

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common

Rare

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Calan SR side effects (more detail)

Commonly used brand name(s)

In the U.S.

Available Dosage Forms:

Therapeutic Class: Cardiovascular Agent

Pharmacologic Class: Calcium Channel Blocker

Chemical Class: Phenylalkylamine

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer