Calan (Verapamil)

(℞) Prescription Required

    Calan (Verapamil) Dosage and Side Effects

    Calan is used to treat high blood pressure and control chest pain known as angina.  The immediate-release tablet form of this medication is also used to prevent and treat irregular heartbeats (arrhythmia).

    Warnings and Precautions

    This medicine controls high blood pressure, arrhythmia, and angina, but it does not cure these conditions. You should continue to take verapamil even if you feel well.

    Before taking verapamil, tell your doctor if you have or have ever had:

    • Any condition that causes food to move through your digestive system more slowly
    • Myasthenia gravis (a condition that causes certain muscles to weaken)
    • Heart failure
    • Heart, liver, or kidney disease
    • Muscular dystrophy (an inherited disease that causes weakening of the muscles).

    You should also tell your doctor you are taking verapamil before any type of surgery, including dental procedures.

    Your doctor will likely start you on a low dose of verapamil and then gradually increase your dose.

    You should keep all appointments with your doctor while taking this medicine. You will need your blood pressure checked regularly to determine how you are responding to verapamil.

    If you take a certain version of the extended-release tablets, you might notice an empty tablet shell in your stool. This does not mean that you did not receive your complete dose of medication.

    Pregnancy and Verapamil

    The safety of verapamil during pregnancy and while breastfeeding has not been determined.

    Side Effects

    You should tell your doctor about all prescription, non-prescription, illegal, recreational, herbal, nutritional, or dietary drugs you are taking, especially:

    • St. John's wort
    • Alpha blockers such as prazosin (Minipress)
    • Antifungals such as itraconazole (Sporanox) and ketoconazole (Nizoral)
    • Aspirin
    • Beta blockers such as atenolol (Tenormin), metoprolol (Lopressor, Toprol XL), nadolol (Corgard), propranolol (Inderal), and timolol (Betimol, Istalol, Timoptic, in Cosopt)
    • Carbamazepine (Tegretol)
    • Cimetidine (Tagamet)
    • Clarithromycin (Biaxin, Prevpac)
    • Cyclosporine (Neoral, Sandimmune)
    • Digoxin (Lanoxin, Lanoxicaps)
    • Disopyramide (Norpace)
    • Erythromycin (E.E.S., E-Mycin, Erythrocin)
    • Flecainide (Tambocor)
    • Certain HIV protease inhibitors such as indinavir (Crixivan), nelfinavir (Viracept), and ritonavir (Norvir, Kaletra)
    • Quinidine (Quinaglute, Quinidex)
    • Lithium (Eskalith, Lithobid)
    • Medications to treat high blood pressure
    • Nefazodone (Dutonin)
    • Phenobarbital
    • Rifampin (Rifadin, Rimactane)
    • Telithromycin (Ketek)
    • Theophylline (Theolair, Uniphyl)

    Other Verapamil Interactions

    Verapamil may change how your body responds to alcohol, causing effects to be more severe and long-lasting.

    You should also talk to your doctor about consuming grapefruit or grapefruit juice while taking this drug.

    Interactions with this medication

    You should tell your doctor about all prescription, non-prescription, illegal, recreational, herbal, nutritional, or dietary drugs you are taking, especially:

    • St. John's wort
    • Alpha blockers such as prazosin (Minipress)
    • Antifungals such as itraconazole (Sporanox) and ketoconazole (Nizoral)
    • Aspirin
    • Beta blockers such as atenolol (Tenormin), metoprolol (Lopressor, Toprol XL), nadolol (Corgard), propranolol (Inderal), and timolol (Betimol, Istalol, Timoptic, in Cosopt)
    • Carbamazepine (Tegretol)
    • Cimetidine (Tagamet)
    • Clarithromycin (Biaxin, Prevpac)
    • Cyclosporine (Neoral, Sandimmune)
    • Digoxin (Lanoxin, Lanoxicaps)
    • Disopyramide (Norpace)
    • Erythromycin (E.E.S., E-Mycin, Erythrocin)
    • Flecainide (Tambocor)
    • Certain HIV protease inhibitors such as indinavir (Crixivan), nelfinavir (Viracept), and ritonavir (Norvir, Kaletra)
    • Quinidine (Quinaglute, Quinidex)
    • Lithium (Eskalith, Lithobid)
    • Medications to treat high blood pressure
    • Nefazodone (Dutonin)
    • Phenobarbital
    • Rifampin (Rifadin, Rimactane)
    • Telithromycin (Ketek)
    • Theophylline (Theolair, Uniphyl)

    Other Verapamil Interactions

    Verapamil may change how your body responds to alcohol, causing effects to be more severe and long-lasting.

    You should also talk to your doctor about consuming grapefruit or grapefruit juice while taking this drug.

    Proper Use of this medication

    For Angina:

    Immediate release formulations: Initially 80-120 milligrams (mg), three to four times a day. It can be increased up to 480 mg per day, in divided doses.

    Extended-release formulations: Initially 180 mg once daily at bedtime. It can be increased up to - 540 mg at bedtime.

    For Hypertension:

    Immediate release formulations: Initially 80 mg three times a day. It can be increased up to 480 mg per day, given in divided doses, although doses greater than 360 mg offer no additional benefit.

    Extended-release formulations: Initially 180-240 mg once daily. It can be increased to 240 mg, twice daily.

    For Migraine:

    Immediate release formulations: Initially 80 mg three times daily. Higher doses have also been used.

    Verapamil Overdose

    If you suspect an overdose, contact a poison control center or emergency room immediately.

    You can get in touch with a poison control center at (800) 222-1222.

    Missed Dose of Verapamil

    If you miss a dose of verapamil, take it as soon as you remember.

    However, if it is almost time for your next dose, skip the missed dose and continue on your regular schedule.

    Do not "double up" to make up for a missed one.

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    The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

    Call us and we can walk you through the entire process! 1-855-776-0079

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