Generic name: nifedipine (oral route) [ nye-FED-i-peen ]
Drug class: Calcium channel blocking agents
Medically reviewed by Drugs.com. Last updated on Feb 23, 2022.
Commonly used brand name(s)
In the U.S.
- Adalat CC
- Afeditab CR
- Nifediac CC
- Nifedical XL
- Procardia XL
- Adalat OROS
- Adalat PA 10
- Adalat PA 20
- Adalat XL
- APO-Nifed PA
- NIFEdipine ER
- pms-NIFEdipine ER
Available Dosage Forms:
- Capsule, Liquid Filled
- Tablet, Extended Release
Therapeutic Class: Cardiovascular Agent
Pharmacologic Class: Calcium Channel Blocker
Chemical Class: Dihydropyridine
Uses for Adalat PA 20
Nifedipine is used alone or together with other medicines to treat severe chest pain (angina) or high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.
Nifedipine is a calcium channel blocker. It works by affecting the movement of calcium into the cells of the heart and blood vessels. As a result, nifedipine relaxes blood vessels and increases the supply of blood and oxygen to the heart while reducing its workload.
This medicine is available only with your doctor's prescription.
Before using Adalat PA 20
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of nifedipine in the pediatric population. Safety and efficacy have not been established.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of nifedipine in the elderly. However, elderly patients are more likely to have age-related kidney, liver, or heart problems which may require caution and an adjustment in the dose for patients receiving nifedipine.
Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- St John's Wort
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Vincristine Sulfate Liposome
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following may cause an increased risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.
- Grapefruit Juice
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Aortic stenosis (narrowing of a valve in your heart) or
- Bowel blockage, severe or
- Congestive heart failure or
- Coronary artery disease or
- Heart attack or
- Hypotension (low blood pressure)—Use with caution. May increase risk of serious side effects.
- Cardiogenic shock (shock caused by heart attack)—Should not be used in patients with these conditions.
- Galactose intolerance (rare hereditary problem) or
- Glucose-galactose malabsorption (rare hereditary problem) or
- Lapp lactase deficiency (rare hereditary problem)—The extended release tablet form of this medicine contains lactose (milk sugar), and should not be given to patients with these conditions.
- Kidney problems or
- Liver problems (including cirrhosis)—Use with caution. The effects of nifedipine may be increased because of the slower removal of the medicine from the body.
Proper use of Adalat PA 20
This section provides information on the proper use of a number of products that contain nifedipine. It may not be specific to Adalat PA 20. Please read with care.
In addition to the use of this medicine, treatment for your high blood pressure may include weight control and changes in the types of foods you eat, especially foods high in sodium (salt). Your doctor will tell you which of these are most important for you. You should check with your doctor before changing your diet.
Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.
Remember that this medicine will not cure your high blood pressure, but it does help control it. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease.
Swallow the extended release tablet whole. Do not break, crush, or chew it. It is best to take this tablet on an empty stomach.
If you are taking the extended-release tablets, part of the tablet may pass into your stool after your body has absorbed the medicine. This is normal and nothing to worry about.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For treatment of chest pain or high blood pressure:
- For oral dosage form (capsules):
- Adults—At first, 10 milligrams (mg) three times a day. Your doctor may increase your dose as needed.
- Children—Use and dose must be determined by your doctor.
- For oral dosage form (extended-release tablets):
- Adults—At first, 30 or 60 milligrams (mg) once a day. Your doctor may increase your dose as needed. However, the dose is usually not more than 90 mg once a day.
- Children—Use and dose must be determined by your doctor.
- For oral dosage form (capsules):
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Precautions while using Adalat PA 20
It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.
You should not use this medicine if you are also taking certain other medications such as carbamazepine (Tegretol®), phenobarbital (Luminal®), phenytoin (Dilantin®), rifabutin (Mycobutin®), rifampin (Rifadin®, Rimactane®), or St. John's Wort. Using these medicines together can cause serious problems. Make sure your doctor knows all of the medications you are taking.
Dizziness, lightheadedness, or fainting may occur, especially when you get up suddenly from a lying or sitting position. These symptoms are more likely to occur when you begin taking this medicine, or when the dose is increased.
This medicine may cause fluid retention (edema) in some patients. Tell your doctor right away if you have bloating or swelling of the face, arms, hands, lower legs, or feet; tingling of the hands or feet; or unusual weight gain or loss.
Do not stop taking this medicine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are using before stopping completely.
Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before having surgery or medical tests. This medicine may affect the results of certain medical tests.
Grapefruits and grapefruit juice may increase the effects of nifedipine by increasing the amount of this medicine in your body. You should not eat grapefruit or drink grapefruit juice while you taking this medicine.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Adalat PA 20 side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
- Bloating or swelling of the face, arms, hands, lower legs, or feet
- difficult or labored breathing
- dizziness or lightheadedness
- fast, irregular, pounding, or racing heartbeat or pulse
- feeling of warmth
- muscle cramps
- rapid weight gain
- shakiness in the legs, arms, hands, or feet
- shortness of breath
- tightness in the chest
- tingling of the hands or feet
- trembling or shaking of the hands or feet
- unusual weight gain or loss
- Blue lips and fingernails
- chest congestion
- chest pain
- coughing that sometimes produces a pink frothy sputum
- decreased urine output
- difficult, fast, or noisy breathing, sometimes with wheezing
- dilated neck veins
- extreme fatigue
- increased sweating
- irregular breathing
- pain or discomfort in the arms, jaw, back, or neck
- pale skin
- severe unusual tiredness or weakness
- troubled breathing
- Black, tarry stools
- bleeding gums
- blood in the eyes
- blood in the urine or stools
- bloody stools
- bluish color
- blurred vision
- body aches or pain
- changes in skin color
- cold sweats
- dark urine
- difficulty with swallowing
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- dry mouth
- dryness or soreness of throat
- ear congestion or pain
- extra heartbeats
- eye pain
- feeling unusually cold
- general tiredness and weakness
- headache, severe and throbbing
- increased urge to urinate during the night
- irritation in the mouth
- large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
- light-colored stools
- nasal congestion
- neck pain
- no blood pressure or pulse
- noisy breathing
- pain in the groin or genitals
- pain or burning while urinating
- painful or difficult urination
- pinpoint red spots on the skin
- puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
- redness and swelling of the gums
- redness in the whites of the eyes
- runny nose
- shakiness and unsteady walk
- sharp back pain just below ribs
- skin rash
- small clicking, bubbling, or rattling sounds in the lung when listening with a stethoscope
- sore throat
- sores, ulcers, or white spots on the lips or in the mouth
- stopping of heart
- swelling around the eyes
- swollen glands
- tender, swollen glands in the neck
- troubled breathing with exertion
- unsteadiness, trembling, or other problems with muscle control or coordination
- unusual bleeding or bruising
- upper right abdominal or stomach pain
- vision changes
- voice changes
- vomiting of blood or material that looks like coffee grounds
- waking to urinate at night
- yellow eyes and skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- feeling of indigestion
- mood changes
- pain in the chest below the breastbone
- redness of the face, neck, arms, and occasionally, upper chest
- Abnormal ejaculation
- bloody nose
- burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
- decreased interest in sexual intercourse
- decreased sexual performance or desire
- difficulty having a bowel movement (stool)
- excess air or gas in stomach or intestines
- feeling of constant movement of self or surroundings
- full feeling
- general feeling of discomfort or illness
- inability to have or keep an erection
- increased need to urinate
- joint stiffness
- leg cramps or pain
- loss in sexual ability, desire, drive, or performance
- passing gas
- passing urine more often
- stuffy nose
- trouble sleeping
- Acid or sour stomach
- ankle, knee, or great toe joint pain
- cracks in the skin
- difficulty with moving
- excessive muscle tone
- fear or nervousness
- feeling sad or empty
- hair loss or thinning of the hair
- increased sensitivity of the skin to sunlight
- itching, pain, redness, swelling, tenderness, or warmth on the skin
- lack of appetite
- lack or loss of strength
- loss of heat from the body
- loss of interest or pleasure
- loss of strength or energy
- loss in sexual ability, desire, drive, or performance
- lower back or side pain
- muscle pain or weakness
- muscle stiffness
- muscle tension or tightness
- pain or burning in the throat
- red, swollen skin
- redness or other discoloration of the skin
- scaly skin
- severe sunburn
- sleepiness or unusual drowsiness
- stomach discomfort, upset, or pain
- swelling of the breasts or breast soreness in both females and males
- trouble concentrating
- unable to sleep
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
More about nifedipine
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- Drug class: calcium channel blocking agents
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- Nifedipine (Advanced Reading)
- Nifedipine Extended-Release Tablets
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