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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: felodipine (fe LOE di peen)
Brand name(s): PLENDIL
GENERIC: not available FAMILY: Calcium Channel Blockers, long-acting
Find the drug label by searching at DailyMed.

Generic drug name: nisoldipine (nis OLD i peen)
Brand name(s): SULAR
GENERIC: available FAMILY: Calcium Channel Blockers, long-acting
Find the drug label by searching at DailyMed.

Generic drug name: verapamil (ver AP a mil)
Brand name(s): CALAN, CALAN SR, COVERA-HS, VERELAN, VERELAN-PM
GENERIC: available FAMILY: Calcium Channel Blockers, long-acting
Find the drug label by searching at DailyMed.

Limited Use [what does this mean?]
Generic drug name: amlodipine (am LOE di peen)
Brand name(s): CONSENSI, KATERZIA, NORVASC
GENERIC: available FAMILY: Calcium Channel Blockers, long-acting
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Limited Use [what does this mean?]
Generic drug name: diltiazem (dil TEE a zem)
Brand name(s): CARDIZEM, CARDIZEM CD, CARDIZEM LA, CARTIA XT, DILACOR XR, DILT-CD, DITZAC, TAZTIA, TAZTIA XT, TIAZAC
GENERIC: not available FAMILY: Calcium Channel Blockers, long-acting
Find the drug label by searching at DailyMed.

Limited Use [what does this mean?]
Generic drug name: isradipine (is RAD ip ene)
Brand name(s):
GENERIC: available FAMILY: Calcium Channel Blockers, long-acting
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Limited Use [what does this mean?]
Generic drug name: nicardipine (nick CARD ip ene)
Brand name(s): CARDENE, CARDENE SR
GENERIC: not available FAMILY: Calcium Channel Blockers, long-acting
Find the drug label by searching at DailyMed.

Limited Use [what does this mean?]
Generic drug name: nifedipine (nye FED i peen)
Brand name(s): ADALAT CC, AFEDITAB CR, PROCARDIA XL
GENERIC: available FAMILY: Calcium Channel Blockers, long-acting
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

These drugs caused fetal harm in animal studies, including delays in growth and development and death. Because of the potential for serious adverse effects to the fetus, these drugs should not be used by pregnant women.

Breast-feeding Warning

 

These drugs are excreted in human milk. Because of the potential for serious adverse effects in nursing infants, you should not take these drugs while nursing.

 

Facts About This Drug [top]

These drugs belong to a family of antihypertensive drugs called calcium channel blockers. They are used primarily to treat chest pain (angina) and also to lower blood pressure (hypertension). Calcium channel blockers control, but do not cure, high blood pressure.

In 1995, Public Citizen’s Health Research Group filed a petition with the FDA to add warnings to the labeling of all calcium channel blockers about the increased risk of heart attack and death. Our petition was based on three...

These drugs belong to a family of antihypertensive drugs called calcium channel blockers. They are used primarily to treat chest pain (angina) and also to lower blood pressure (hypertension). Calcium channel blockers control, but do not cure, high blood pressure.

In 1995, Public Citizen’s Health Research Group filed a petition with the FDA to add warnings to the labeling of all calcium channel blockers about the increased risk of heart attack and death. Our petition was based on three well-conducted observational research studies.[1],[2],[3],[4] Observational studies are frequently criticized by doctors who do not understand this type of research. Most of what we know about adverse drug reactions and what we are likely to learn in the future comes from observational research. This type of research was used to show the link between cigarette smoking and lung cancer.

Our petition helped to bring about important labeling changes in February 1996 on one of the calcium channel blockers, the short-acting form of nifedipine (ADALAT CC, PROCARDIA, PROCARDIA XL). The labeling for this form of nifedipine now warns doctors that this product should not be used for the treatment of high blood pressure.

Despite the recommendations of the National Institutes of Health’s National Heart, Lung, and Blood Institute that diuretics should be used first in the treatment of mild-to-moderate high blood pressure, calcium channel blockers have been the largest-selling family of high-blood-pressure-lowering drugs in the U.S.[5] Over 30 million prescriptions were dispensed in 2002 for the calcium channel blocker amlodipine.

A major study published in 2002 known as the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT for short) found that the older thiazide diuretic chlorthalidone (HYGROTON) was superior to the calcium channel blocker amlodipine in the treatment of high blood pressure. This was the largest and longest trial of its kind, with patients being followed for four to eight years.[6]

In 2005, The Lancet published a study examining the effects of intensified blood pressure control (systolic blood pressure < 130 mm HG, diastolic blood pressure < 80 mm Hg) on progression to end stage kidney (renal) disease. In non-diabetic patients with kidney disease that included protein in the urine on ACE inhibitor therapy, adding a dihydropyridine calcium channel blocker to further reduce blood pressure did not offer any additional protection against kidney disease.[7]

Each calcium channel blocker differs in the likelihood of harmful adverse effects. Although nisoldipine and nifedipine, which are in a distinct chemical class of calcium channel blockers, are less likely than verapamil to cause constipation, they are more apt to cause dizziness, flushing, headaches, rapid heartbeat, and swelling of legs and feet than are other calcium channel blockers.[8] These adverse effects can seriously limit use.

If you have high blood pressure, the best way to reduce or eliminate your need for medication is by improving your diet, losing weight, exercising and decreasing your salt and alcohol intake. Mild hypertension can be controlled by proper nutrition and exercise. If these measures do not lower your blood pressure enough and you need medication, hydrochlorothiazide (ESIDRIX, HYDRODIURIL, MICROZIDE), a water pill, is the drug of choice, starting with a low dose of 12.5 milligrams daily. It also costs less than other blood pressure drugs.

There is growing evidence that thiazide diuretics, such as hydrochlorothiazide, significantly decrease the rate of bone mineral loss in both men and women because they reduce the amount of calcium lost in the urine.[9] Research now suggests that thiazide diuretics may protect against hip fracture.[10]

If your high blood pressure is more severe, and hydrochlorothiazide alone does not control it, another family of high-blood-pressure-lowering drugs may be added to your treatment. In this case, your doctor would prescribe the hydrochlorothiazide and the second drug separately, with the dose of each drug adjusted to meet your needs, rather than using a product that combines the drug in a fixed combination.

Whatever drugs you take for high blood pressure, once your blood pressure has been normal for a year or more, a cautious decrease in dose and renewed attention to nondrug treatment may be worth trying, according to The Medical Letter.[11]

An editorial in the British Medical Journal (BMJ) stated: “Treatment of hypertension is part of preventive medicine and like all preventive strategies, its progress should be regularly reviewed by whoever initiates it. Many problems could be avoided by not starting antihypertensive treatment until after prolonged observation. ...Patients should no longer be told that treatment is necessarily for life: the possibility of reducing or stopping treatment should be mentioned at the outset.”[12]

The May 2012 issue of Worst Pills, Best Pills News highlighted a recent BMJ study indicating that patients taking several types of commonly used antihypertensive medications are at increased risk of developing gout, a type of arthritis.

The BMJ study also showed that a small number of other antihypertensive drugs appear to have the opposite effect, decreasing the risk of gout.

All patients should be informed of the risk of gout with diuretics, beta-blockers, angiotensin-converting enzyme inhibitors and non-lorsartan angiotensin II receptor blockers when starting these medications or increasing their dosages.[13]

In 2011, the Canadian Medical Association Journal published results from a Canadian study on the use of macrolide antibiotics and calcium channel blocker drugs in elderly patients. The study found that patients using this drug combination therapy experienced an increased risk of hospitalization for hypotension or low blood pressure. According to the article, the risk of hypotension occurred with both erythromycin (E.E.S., E.E.S. 200, E.E.S. 400, ERYC, ERYPED, ERY-TAB, ERYTHROCIN, PCE, PEDIAMYCIN, PEDIAMYCIN 400) and clarithromycin (BIAXIN, BIAXIN XL, PREVPAC [a drug combination used to treat peptic ulcer disease that also contains the antibiotic amoxicillin and the stomach acid-suppressing drug lansoprazole]).[14]

In 2013, the Journal of the American Medical Association published data from another Canadian study on the use of macrolide antibiotics and calcium channel blocker drugs. This study looked at the use of clarithromycin versus azithromycin (ZITHROMAX, ZMAX) in elderly patients taking calcium channel blockers. The purpose of the study was to evaluate patients for the risk of hospitalization for acute kidney injury or hypotension, as well as all-cause mortality. The study showed that there were small but statistically significant greater risks of hospitalization for acute kidney injury or hypotension and of death in patients taking clarithromycin with a calcium channel blocker drug compared to those taking azithromycin with a calcium channel blocker.[15]

Based on these study results, patients should always avoid taking clarithromycin and erythromycin if they are also taking a calcium channel blocker.

Before You Use This Drug [top]

Do not use if you have or have had:

  • severe hypotension

Tell your doctor if you have or have had:

  • allergies to drugs
  • aortic stenosis
  • diabetes
  • heart, kidney, or liver problems
  • low potassium levels in your blood
  • mental depression
  • narrowing of GI tract (with nifedipine only)
  • low blood pressure
  • pregnancy or are breast-feeding

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products. Be sure to include the name of any eye drops that you use.

If you are taking a beta-blocker, your doctor may gradually take you off of it before starting a calcium channel blocker.

When You Use This Drug [top]

  • Learn to take your pulse, and get immediate help if your pulse slows to 50 beats per minute or slower, even if you are feeling well.
  • Periodically check your blood pressure one or two hours after you take a dose, and again eight hours after your last dose.
  • Follow a diet recommended by your doctor.
  • Have your doctor suggest exercises that avoid overexertion.
  • Do not stop taking calcium channel blockers suddenly. Contact your doctor for a schedule to decrease your drug gradually.
  • You may feel dizzy when rising from a lying or sitting position. If you are lying down, hang your legs over the side of the bed for a few minutes, then get up slowly. When getting up from a chair, stay by the chair until you are sure that you are not dizzy. 
  • If you plan to have any surgery, including dental, tell your doctor that you take this drug.
  • See your dentist frequently for teeth cleaning to prevent gum problems.
  • Do not take other drugs without talking to your doctor first—especially drugs for asthma, colds, cough, diet, hay fever, or sinus problems.

How to Use This Drug [top]

  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Swallow capsule or tablet whole. Do not break, chew, or crush long-acting forms of this drug.
  • Be aware that the shell, empty of the drug, of some forms will pass in your stool.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

The use of  beta blockers may increase the likelihood of congestive heart failure, severe low blood pressure, or worsening of chest pain (angina).

AGENERASE, alfuzosin, amprenavir, cimetidine, delavirdine, DILANTIN, LANOXICAPS, LANOXIN, mizolastine, phenytoin, RESCRIPTOR, UROXATRAL.

The drugs listed above have reported interactions with nifedipine. Not all of these interactions may have been reported for the other, newer calcium channel blockers listed in this section. Always ask your doctor and pharmacist about specific interactions for the calcium channel blocker you are taking.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • chest pain
  • dizziness
  • irregular heartbeat
  • pounding headache[16]
  • fiery-red discoloration of knees or ankles[16]
  • swelling of legs, ankles, or feet
  • yellowing of skin or eyes
  • problems urinating[17]
  • breathing difficulty
  • coughing or wheezing
  • skin rash
  • bleeding, tender, or swollen gums
  • fainting
  • painful swollen joints (with nifedipine only; unknown for others)
  • trouble seeing (with nifedipine only; unknown for others)

Call your doctor if these symptoms continue:

  • drowsines
  • dry mouth
  • flushing and feeling of warmth
  • headache
  • indigestion
  • muscle cramps
  • nausea
  • numbness
  • redness, heat, or pain in the fingers (This is more apt to happen during warm weather or while in bed at night.[18] If this occurs, dip your hands in cold water.)
  • skin rash
  • feeling of weakness
  • constipation
  • diarrhea
  • dizziness, lightheadedness
  • increased appetite and/or weight gain

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • blood pressure
  • heart function tests, such as electrocardiogram (ECG, EKG)
  • heart rate
  • kidney function tests
  • liver function tests
  • potassium blood levels
  • neurological tests

last reviewed March 31, 2021