HealthyCanada.com

Verapamil is most commonly used (alone or in combination with other medications) to lower blood pressure in people with high blood pressure (hypertension) and to prevent and decrease the frequency of angina (chest pain) attacks. It is also be used to treat arrhythmias (irregular heartbeats).

Is there any reason why I shouldn't take this drug?

You should not use this drug if you are allergic to it if you have heart rhythm conditions such as second or third degree heart block or sick sinus syndrome. Before taking this medication tell your doctor specifically if you have or have ever had:

• congestive heart failure
• problems with stomach obstruction
• problems with your kidney or liver
• swelling (edema) in the ankles or feet
• low blood pressure (hypotension)
• slow heart rate
• muscular dystrophy
• heart rhythm condition called Wolff-Parkinson White or Lown-Ganong-Levine syndrome

What about possible side effects?

The most common side effects are:

• constipation
• feeling dizzy
• headache
• leg and ankle swelling
• flushing
• feeling tired and weak
• slow heartbeat
• upset stomach

Other less common side effects:

• rash
• swelling of the gums
• rare cases of breast tenderness or swelling in men (gynecomastia)
• rare problems with kidney or liver - call your doctor if you experience unexplained nausea vomiting stomach pain fatigue loss of appetite dark urine yellowing of the skin and/or eyes

This is not a complete list of side effects. If you are concerned about these or other unusual symptoms while taking this medication ask your doctor and/or pharmacist for more information and advice.

What if I am taking other drugs?

Always provide your doctor with a list of all other drugs you are taking (including over-the-counter medications and herbal/natural products) as they may interact and change the safety or effectiveness of either drug. Tell your doctor specifically if you are taking any of these drugs as he/she may need to make changes or monitor you more closely:

• other medications to treat high blood pressure or angina - may increase your chance of experiencing low blood pressure or having other similar side effects
• if you are taking this drug to treat high blood pressure be careful of certain over-the-counter medicines that may increase your blood pressure - these include some cough and cold medicines; ask your doctor or pharmacist for more information
• beta-blockers (e.g. metoprolol atenolol propranolol) - this combination should be used with caution and with close monitoring; when used together you may have an increased chance for side effects especially a slow heartbeat
• ketoconazole itraconazole fluconazole erythromycin cimetidine clarithromycin amiodarone HIV protease inhibitors (e.g. ritonavir) - may increase the amount of verapamil in your blood
• quinidine procainamide amiodarone disopyramide digoxin cyclosporine theophylline simvastatin carbamazepine atorvastatin lovastatin lithium terazosin - verapamil can increase the amount of these drugs in the blood and increase the chance for side effects
• rifampin St. John's Wort phenytoin - may see a decrease in the amount of verapamil in the blood

This is not a complete list of drug interactions. Ask your doctor or pharmacist to review your list of medications.

Other information:

Special Instructions and Follow-up

If you are taking this drug for high blood pressure or angina your blood pressure should be checked regularly to see how well verapamil is working. Your doctor may ask you to check your pulse (heart rate). Ask your pharmacist or doctor to teach you how to take your pulse and ask what "number" your heart rate should be. If your pulse is faster or slower than it should be call your doctor.

This drug (in the long-acting forms) will not work to decrease angina attacks at the time that they happen. You should also have a medication called nitroglycerin to use when you have episodes of chest pain.

If you have congestive heart failure and you are taking this medication this should be avoided in most cases. This medication can cause your symptoms of heart failure to get worse.

As you see an improvement in your chest pain because of taking verapamil you may be tempted to exercise vigorously - check with your doctor first to determine whether you can safely exercise and/or how intensely you should be exercising.

If you are undergoing medical or dental surgery tell your doctor or dentist you are taking verapamil as some anesthetics may cause your blood pressure to drop.

If you are taking Chronovera do not crush or chew the capsule. It should be swallowed whole. This medication should generally be taken at bedtime to work properly. Do not be alarmed if you notice the outer shell of the capsule in your stool the medication has still been absorbed.

Children: If prescribed a reduced dose may be required.

Seniors: Are more sensitive to side effects and lower doses are usually necessary.

Pregnant women: Generally not prescribed. Safer drugs are available. Talk to your doctor.

Women who are nursing: Drug passes into the breast milk. Talk to your doctor.

People who drive or operate machinery: Should not do so until they know how this drug affects them personally.

Overdose: A large overdose of this medicine could cause severe drowsiness dizziness or a very low heart rate. If you experience any unusual reactions or if you seriously exceed the recommended dosage call your doctor or 911.

Stopping the drug: Talk to your doctor before you stop taking this drug. Stopping the drug will likely cause your blood pressure to increase or your other symptoms of chest pain (angina) to return.

If you miss a dose: Talk to your pharmacist as it may differ depending on whether you are taking the short or long acting form of the medication. Do not take a double dose.

Storage conditions: Closed container; cool dry location away from excess moisture (not in the bathroom) and light; always away from children.

Alcohol: If you drink then drink with caution. This medication may increase the effects of alcohol in your body making you more at risk of intoxication. As well drinking too much alcohol may cause a decrease in blood pressure and dizziness.

Dietary precautions: Avoid drinking grapefruit juice or eating grapefruit as it may decrease the breakdown of verapamil in the body cause higher levels in the blood and increase the chance for side effects.