Verapamil tablets
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What are verapamil tablets?
VERAPAMIL (Calan®, Isoptin®) is a calcium-channel blocker. By relaxing blood vessels, it can improve blood flow to the heart. Verapamil reduces attacks of chest pain (angina); lowers blood pressure (treats hypertension); and controls heart rate in certain conditions. Generic verapamil tablets are available.
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
• constipation problems
• heart or blood vessel disease
• heart rhythm disturbances such as sick sinus syndrome, ventricular arrhythmias, Wolff-Parkinson-White syndrome, or Lown-Ganong-Levine syndrome
• liver or kidney disease
• neuromuscular disease such as muscular dystrophy
• slow or irregular heartbeat
• an unusual or allergic reaction to verapamil, other medicines, foods, dyes, or preservatives
• pregnant or trying to get pregnant
• breast-feeding
How should I take this medicine?
Take verapamil tablets by mouth. Follow the directions on the prescription label. Swallow the tablets with a drink of water. Do not take with grapefruit juice. If verapamil upsets your stomach, you can take it with food or milk. Take your doses at regular intervals. Do not take your medicine more often then directed. Do not stop taking except on your prescriber's advice.
Contact your pediatrician or health care professional regarding the use of this medicine in children. Special care may be needed.
Elderly patients over 65 years old may have a stronger reaction to this medicine and need smaller doses.
What drug(s) may interact with verapamil?
Do not take Verapamil with any of the following:
• astemizole
• cisapride
• disopyramide
• dofetilide
• grapefruit juice
• pimozide
• terfenadine
Verapamil may also interact with the following medications:
• alcohol
• alfuzosin
• alosetron
• antiinflammatory drugs (NSAIDs, such as ibuprofen)
• barbiturates such as phenobarbital
• bosentan
• caffeine
• certain antibiotics (clarithromycin, erythromycin, telithromycin, troleandomycin)
• certain medicines used to treat cancer
• certain medicines to treat migraine (ergotamine, dihydroergotamine, methysergide)
• cevimeline
• cilostazol
• cimetidine
• clonidine
• cyclosporine
• doxercalciferol
• fentanyl
• galantamine
• herbal or dietary supplements such as ginger, ginkgo biloba, ginseng, hawthorn, ma huang (ephedra), melatonin, St. John's wort, red yeast rice
• lithium
• local anesthetics or general anesthetics
• medicines for anxiety or difficulty sleeping (examples: alprazolam, buspirone, midazolam, triazolam)
• medicines for depression or mental problems (examples: imipramine, fluoxetine, fluvoxamine, nefazodone, ziprasidone)
• medicines for fungal infections (fluconazole, itraconazole, ketoconazole, voriconazole)
• medicines for heart-rhythm problems (amiodarone, digoxin, flecainide, procainamide, quinidine)
• medicines for high cholesterol (atorvastatin, cerivastatin, colesevelam, lovastatin, simvastatin)
• medicines for high blood pressure or heart problems
• medicines for HIV infection or AIDS
• medicines for prostate problems
• medicines for seizures (carbamazepine, clonazepam, ethosuximide, oxcarbazepine, phenobarbital, phenytoin, primidone, zonisamide)
• methadone
• methylprednisolone
• monoamine oxidase inhibitors (Azilect®, Eldepryl®, Emsam®, Marplan®, Nardil®, Parnate®, Zelapar™)
• rifampin, rifabutin or rifapentine
• sildenafil
• sirolimus
• sulfinpyrazone
• tacrolimus
• theophylline or aminophylline
• water pills (diuretics)
• yohimbine
• zafirlukast
• zileuton
Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.
What should I watch for while taking verapamil?
Check your blood pressure and pulse rate regularly; this is important while you are taking verapamil. Ask your prescriber or health care professional what your blood pressure and pulse rate should be and when you should contact him or her.
You may feel dizzy or lightheaded. Do not drive, use machinery, or do anything that needs mental alertness until you know how verapamil affects you. To reduce the risk of dizzy or fainting spells, do not sit or stand up quickly, especially if you are an older patient. Alcohol can make you more dizzy or increase flushing and rapid heartbeats. Avoid alcoholic drinks.
Do not suddenly stop taking verapamil. Ask your prescriber or health care professional how to gradually reduce the dose.
If you are going to have surgery, tell your prescriber or health care professional that you are taking verapamil.
What side effects may I notice from taking verapamil?
Side effects that you should report to your prescriber or health care professional as soon as possible:
More common:
• dizziness
• slow heartbeat (less than 50 beats per minute)
• lightheadedness
• swelling of the legs or ankles
Rare or uncommon:
• difficulty breathing
• fast heartbeat, palpitations, irregular heartbeat, chest pain, or
• fainting
• skin rash
Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):
• constipation
• facial flushing
• headache
• nausea, vomiting
• sexual dysfunction
• weakness or tiredness
Where can I keep my medicine?
Keep out of the reach of children in a container that small children cannot open.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Protect from light. Keep container tightly closed.
Important Disclaimer: The drug information provided here is for educational purposes only. It is intended to supplement, not substitute for, the diagnosis, treatment and advice of a medical professional. This drug information does not cover all possible uses, precautions, side effects and interactions. It should not be construed to indicate that this or any drug is safe for you. Consult your medical professional for guidance before using any prescription or over the counter drugs.
