Calan
Generic Name: Verapamil
What is Calan?
Calan is used to treat chest pain (angina) that occurs either while at rest or during exertion. Both kinds of chest pain are due to clogged heart arteries. Calan is also used to treat irregular heartbeat and high blood pressure.What is the most important information I should know about Calan?
If you have high blood pressure, you must take Calan regularly for it to be effective. Since blood pressure declines gradually, it may take several weeks before you get the full benefit of Calan. Continue taking Calan even if you are feeling well. Calan does not cure high blood pressure; it only keeps it under control.Be sure to follow up with your doctor regularly to monitor your liver function. If you already have liver problems, notify your doctor so he or she may determine if the dose of Calan is appropriate for you.
It is important to let your doctor know of any heart conditions, diseases, or heartbeat irregularities before starting this medication.
Who should not take Calan?
Do not take Calan if you have low blood pressure or certain types of heart disease or heartbeat irregularities. Do not take Calan if you are allergic to any of its ingredients.What should I tell my doctor before I take the first dose of Calan?
Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Calan. Also, talk to your doctor about your complete medical history, especially if you have any heart problems, kidney disease, liver disease, muscle weakness due to a condition known as myasthenia gravis, or rapidly progressive muscle weakness due to an inherited disorder called Duchenne's muscular dystrophy. Tell your doctor if you are also using drugs known as beta-blockers.What is the usual dosage?
The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.The dose of Calan must be individualized. In general, dosages of Calan should not exceed 480 milligrams (mg) per day.
Angina
Adults: The usual initial dose is 80-120 mg, three times a day. Lower doses of 40 mg three times a day may be used in the elderly or those with decreased liver function. Your doctor may increase the dosage either daily or weekly until the desired response is seen.
Blood Pressure
Adults: The usual dose when used alone is 80 mg, three times a day. Smaller individuals and the elderly may take smaller doses of 40 mg three times a day.
Irregular Heartbeat
Adults: The usual dose in people who are also on digitalis ranges from 240-320 mg per day, divided into three or four doses. In people who are not taking digitalis, doses range from a total of 240-480 mg per day, divided into three or four doses.
How should I take Calan?
Calan can be taken with or without food.What should I avoid while taking Calan?
Try not to miss any doses. Take Calan exactly as prescribed even if you are feeling well. If the drug is not taken regularly, your condition can get worse.Do not stop taking Calan abruptly without consulting with your doctor. A slow reduction in dose may be required.
What are possible food and drug interactions associated with Calan?
If Calan is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Calan with the following: ACE inhibitors, alcohol, amiodarone, aspirin, beta-blockers, carbamazepine, chloroquine, cimetidine, cyclosporine, dantrolene, digitalis, disopyramide, erythromycin, flecainide, furosemide, glipizide, grapefruit juice, hydrochlorothiazide, imipramine, lithium, minoxidil, nitrates (such as isosorbide dinitrate), prazosin, phenobarbital, phenytoin, quinidine, rifampin, ritonavir, telithromycin, or theophylline.What are the possible side effects of Calan?
Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.Side effects may include: congestive heart failure, constipation, dizziness, fatigue, fluid retention, headache, low blood pressure, nausea, rash, shortness of breath, slow heartbeat, upper respiratory tract infection
Can I receive Calan if I am pregnant or breastfeeding?
The effects of Calan during pregnancy are unknown. Calan is excreted in human milk and should be discontinued while breastfeeding because of the potential adverse reactions in breastfed infants. Tell your doctor immediately if you are pregnant, plan to become pregnant, or are breastfeeding.What should I do if I miss a dose of Calan?
Take it as soon as you remember. If it is almost time for your next dose, skip the one you missed and go back to your regular schedule. Do not take two doses at once.How should I store Calan?
Store at room temperature away from heat, light, and moisture.
I'm Beth Isaac, PharmD. Welcome to PDR Health!
