Nifedipine is in a group of drugs called calcium channel blockers. It works by relaxing the muscles of your heart and blood vessels.
Nifedipine is used to treat hypertension (high blood pressure) and angina (chest pain).
Nifedipine may also be used for purposes not listed in this medication guide.
What is the most important information I should know about nifedipine?
You should not use nifedipine if you have severe coronary artery disease, or if you have had a heart attack within the past 2 weeks.
Before taking nifedipine, tell your doctor if you have kidney or liver disease, a blockage in your digestive tract (stomach or intestines), a history of stomach surgery, coronary artery disease, underactive thyroid, diabetes, or congestive heart failure.
If you need surgery, tell the surgeon ahead of time that you are using nifedipine. You may need to stop using the medicine for a short time.
Do not stop taking nifedipine without first talking to your doctor, even if you feel fine. Stopping suddenly may make your condition worse. High blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life.
Before taking this medicine
You should not use this medicine if you are allergic to nifedipine, if you have severe coronary artery disease, or if you have had a heart attack within the past 2 weeks.
To make sure nifedipine is safe for you, tell your doctor if you have:
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severe COPD (chronic obstructive pulmonary disease);
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kidney disease;
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congestive heart failure; or
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if you take other medications, especially an antibiotic or antifungal medicine, an antidepressant, heart or blood pressure medicine, or drugs to treat HIV/AIDS or hepatitis C.
It is not known whether nifedipine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.
Nifedipine can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.
The nifedipine extended-release tablet may contain lactose. Talk to your doctor before using this form of nifedipine if you have galactose intolerance, or severe problems with lactose (milk sugar).
How should I take nifedipine?
Take nifedipine exactly as prescribed by your doctor. Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not take this medicine in larger or smaller amounts or for longer than recommended.
You may need to take an extended-release tablet on an empty stomach. Follow the directions on your medicine label about taking this medication with or without food.
Do not crush, chew, or break a nifedipine extended-release tablet. Swallow it whole.
Your blood pressure will need to be checked often and you may need other blood tests at your doctor"s office.
Some tablet forms of nifedipine are made with a shell that is not absorbed or melted in the body. Part of the tablet shell may appear in your stool. This is a normal side effect of nifedipine and will not make the medication less effective.
If you need surgery, tell the surgeon ahead of time that you are using nifedipine. You may need to stop using the medicine at least 36 hours before surgery.
You may have very low blood pressure while taking this medication. Call your doctor if you are sick with vomiting or diarrhea, or if you are sweating more than usual.
If you are also taking a beta-blocker (atenolol, carvedilol, labetalol, metoprolol, nadolol, nebivolol, propranolol, sotalol, and others) you should not stop using the beta-blocker suddenly or you could have serious heart problems that will not be prevented by nifedipine. Follow your doctor"s instructions about tapering your beta-blocker dose.
You should not stop using nifedipine suddenly. Stopping suddenly may make your condition worse.
If you are being treated for high blood pressure, keep using this medication even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life.
Store at room temperature away from moisture, heat, and light.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid?
Grapefruit and grapefruit juice may interact with nifedipine and lead to unwanted side effects. Discuss the use of grapefruit products with your doctor.
Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.
Nifedipine side effects
Get emergency medical help if you have any signs of an allergic reaction to nifedipine: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
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worsening angina;
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a light-headed feeling, like you might pass out;
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pounding heartbeats or fluttering in your chest;
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chest pain or heavy feeling, pain spreading to the jaw or shoulder, nausea, sweating, general ill feeling;
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swelling in your ankles or feet; or
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upper stomach pain, jaundice (yellowing of the skin or eyes).
Common nifedipine side effects may include:
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mild dizziness;
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flushing (warmth, redness, or tingly feeling);
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weakness, headache, mood changes;
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heartburn, nausea;
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tremors, muscle cramps; or
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cough, wheezing, sore throat, stuffy nose.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
See also: Side effects (in more detail)
Nifedipine dosing information
Usual Adult Dose of Nifedipine for Hypertension:
Initial dose:
Extended release tablets: 30 to 60 mg orally once a day
Dosage can be increased gradually every 7 to 14 days.
Maximum dose:
Adalat (R) CC: 90 mg/day
Procardia XL (R): 120 mg/day
Usual Adult Dose for Migraine Prophylaxis:
Initial dose:
Extended release tablets: 30 mg orally once a day
Immediate release capsules: 10 mg orally 3 times a day
Usual Adult Dose of Nifedipine for Angina Pectoris Prophylaxis:
Initial dose:
Extended release tablets: 30 to 60 mg orally once a day
Immediate release capsules: 10 mg orally 3 times a day
Dosage can be increased gradually every 7 to 14 days.
Maintenance dose:
Immediate release capsules: 10 to 30 mg orally 3 to 4 times a day
Maximum dose:
Extended release tablets:
Adalat (R) CC: 90 mg/day
Procardia XL (R): 120 mg/day
Immediate release capsules: 180 mg/day
Usual Adult Dose for Congestive Heart Failure:
Initial dose:
Procardia XL (R): 30 to 60 mg orally once a day
Adalat (R) CC: 30 mg orally once a day
Usual Adult Dose of Nifedipine for Premature Labor:
The tocolytic properties of nifedipine have been evaluated in several studies. Doses used in these studies have ranged from 10 to 40 mg as an initial "one time" dose. Subsequent dosages have ranged from 10 to 20 mg every 6 to 8 hours as needed and tolerated to delay delivery.
Immediate release capsules are not approved by the FDA for the treatment of premature labor. In addition, their use in patients with hypertension is not recommended because of data that have revealed evidence of increased risk of adverse cardiovascular events associated with the use of short-acting nifedipine in patients with hypertension. Elderly patients with coronary artery disease may be at particular risk (unlikely to pertain to pregnant women).
Usual Pediatric Dose for Hypertensive Emergency:
Children:
Immediate release capsules: 0.25 to 0.5 mg/kg/dose (maximum 10 mg/dose) repeated every 4 to 6 hours if necessary
Maximum dose: 1 to 2 mg/kg/day
Initial doses less than or equal to 0.25 mg/kg/dose may result in a less dramatic decrease in blood pressure and be safer than larger initial doses. Some centers use initial doses of 0.1 mg/kg/dose.
Usual Pediatric Dose for Hypertension:
Extended release tablets:
Children: 0.25 to 0.5 mg/kg/day in 1 to 2 divided doses; dose should be titrated to effect
Maximum dose: 3 mg/kg/day up to 120 mg/day (or 180 mg/day in some centers)
Adolescents:
Initial dose: 30 mg orally once a day
Usual Pediatric Dose for Hypertrophic Cardiomyopathy:
Children: 0.6 to 0.9 mg/kg/24 hours in 3 to 4 divided doses
What other drugs will affect nifedipine?
Other drugs may interact with nifedipine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
