How does this medication work? What will it do for me?

Candesartan belongs to a family of medications known as angiotensin II receptor blockers. It is used to lower high blood pressure in adults and children over 6 years of age, and to treat heart failure in adults. It works by relaxing blood vessels.

Angiotensin II is a chemical that the body releases to cause the constriction of blood vessels. Candesartan blocks the action of angiotensin II, resulting in the relaxation of the blood vessels. This relaxation causes the blood pressure to decrease. It takes about 2 weeks for this medication to begin lowering blood pressure, and about 4 weeks for it to reach its full effect.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

8 mg
Each pink, capsule-shaped tablet, engraved with "C|8" on both sides, contains 8 mg of candesartan cilexetil. Nonmedicinal ingredients: carmellose calcium, microcrystalline cellulose, lactose monohydrate, magnesium stearate, pregelatinized starch, poloxamer 188, povidone, red iron oxide.

16 mg
Each pink, capsule-shaped tablet, engraved with "16" on one side and "C|C" on the other, contains 16 mg of candesartan cilexetil. Nonmedicinal ingredients: carmellose calcium, microcrystalline cellulose, lactose monohydrate, magnesium stearate, pregelatinized starch, poloxamer 188, povidone, red iron oxide.

32 mg
Each pink, capsule-shaped tablet, engraved with "32" on one side and "C|C" on the other, contains 32 mg of candesartan cilexetil. Nonmedicinal ingredients: carmellose calcium, microcrystalline cellulose, lactose monohydrate, magnesium stearate, pregelatinized starch, poloxamer 188, povidone, red iron oxide.

How should I use this medication?

For adults with high blood pressure, the usual recommended starting dose of candesartan is 16 mg once daily. Reductions in blood pressure are often seen within 2 weeks, and the full effects on blood pressure are seen in about 4 weeks. Your doctor may decide to increase the dose to 32 mg once a day if your blood pressure has not decreased enough. A diuretic (water pill) may also be added to help reduce blood pressure.

For children with high blood pressure, the dose of candesartan is based on body weight. The usual starting dose for children weighing less than 50 kg is 4 mg once daily. This dose may be increased to a maximum daily dose of 8 mg. For children weighing more than 50 kg, the usual starting dose is 8 mg once daily. This dose may be increased to a maximum daily dose of 16 mg.

For adults with heart failure the usual recommended starting dose of candesartan is 4 mg once daily. Depending on how well you tolerate the medication, the dose may be doubled every 2 weeks to a maximum daily dose of 32 mg.

Candesartan should be taken at approximately the same time each day, with or without food.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important that this medication be taken exactly as prescribed by your doctor. If you miss a dose but remember within 12 hours, take it as soon as possible and continue with your regular schedule. If more than 12 hours have passed since your usual dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

It is important to take this medication regularly and to follow your doctor's instructions regarding monitoring your blood pressure to ensure that you receive the maximum benefit from the medication.

Store this medication at room temperature (in a dry place and not in the bathroom) in its original package and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not take candesartan if you:

  • are allergic to candesartan or to any of the ingredients of the medication
  • have experienced angioedema as a reaction to any Angiotensin Receptor Blocker (ARB)
  • are or planning to become pregnant
  • are breastfeeding
  • have diabetes and are taking the medication aliskiren
  • have galactose intolerance or glucose malabsorption (a rare hereditary disease)

This medication should not be used in children less than 1 year of age.

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • back or leg pain
  • cough
  • diarrhea
  • dizziness
  • ear congestion or pain
  • fever
  • head congestion
  • headache
  • muscle cramps
  • nasal congestion
  • runny or stuffy nose
  • sneezing
  • sore throat

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • chest pain
  • dizziness, lightheadedness, or fainting
  • fast, slow, or irregular heartbeat
  • rash
  • signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood,  bleeding gums, cuts that don’t stop bleeding)
  • signs of kidney problems (e.g., increased urination at night, decreased urine production, blood in the urine)
  • signs of kidney failure (e.g., decreased urine production, swelling, fatigue, abdominal pain)
  • signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
  • signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
  • signs of too much potassium in the body (e.g., irregular heartbeat, muscle weakness, generally feeling unwell)
  • swelling of the hands, feet, or ankles
  • unexplained muscle pain, tenderness, or weakness

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort
  • signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
  • signs of stroke (e.g., sudden or severe headache; sudden loss of coordination; vision changes; sudden slurring of speech; or unexplained weakness, numbness, or pain in arm or leg)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

HEALTH CANADA ADVISORY

February 4, 2014

Health Canada has issued new restrictions concerning the use of candesartan. To read the full Health Canada Advisory, visit Health Canada's web site at www.hc-sc.gc.ca.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Drowsiness/reduced alertness: Candesartan may cause drowsiness or dizziness, affecting your ability to drive or operate machinery. Avoid these and other hazardous tasks until you have determined how this medication affects you.

Kidney problems: Candesartan may affect kidney function, especially for people who already have kidney problems. If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver function: Candesartan is removed from the body by the liver. Rarely, it may cause liver problems. If you have liver disease or decreased liver function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Low blood pressure: Occasionally, a larger-than-expected decrease in blood pressure occurs after taking candesartan. In some cases, this happens after the first dose. It is more likely to occur if you take diuretics or the medication aliskiren, have a reduced salt intake, are on dialysis, or are experiencing diarrhea or vomiting. Blood pressure should be monitored more often in these situations. Those with low blood pressure or those just starting to take this medication should move slowly from a reclining to an upright position to reduce the risk of dizziness.

Potassium levels: This medication may affect potassium levels in the blood, especially when used for heart failure, or when taken with other medications called ACE inhibitors or diuretics such as spironolactone. Your doctor will monitor your potassium levels while on this medication. Avoid using salt substitutes that contain potassium while you are taking candesartan.

Pregnancy: Candesartan may cause severe harm to an unborn fetus and should not be used during pregnancy. If you discover you are pregnant while taking this medication, stop taking it and tell your doctor at once.

Breast-feeding: It is not known if candesartan passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for  the treatment of hypertension in children less than 6 years of age and for the treatment of heart failure in children less than 18 years of age.

What other drugs could interact with this medication?

There may be an interaction between candesartan and any of the following:

  • alfuzosin
  • aliskiren
  • amifostine
  • amphetamines (e.g., dextroamphetamine, lisdexamphetamine)
  • angiotensin converting enzyme inhibitors (ACEIs; captopril, enalapril, ramipril)
  • angiotensin receptor blockers (ARBs; e.g., candasartan, irbesartan, losartan)
  • barbiturates (e.g., secobarbital, phenobarbital)
  • beta-adrenergic blockers (e.g., atenolol, propranolol, sotalol)
  • brimonidine
  • calcium channel blockers (e.g., amlodipine, diltiazem, nifedipine, verapamil)
  • canagliflozin
  • celecoxib
  • clonidine
  • cyclosporine
  • dipyridamole
  • diuretics (water pills; e.g., furosemide, hydrochlorothiazide, triamterene)
  • guanfacine
  • heparin
  • hydralazine
  • isosorbide dinitrate or isosorbide mononitrate
  • levodopa
  • lithium
  • low molecular weight heparins (e.g., dalteparin, enoxaparin, tinzaparin)
  • methyldopa
  • methylphenidate
  • monoamine oxidase inhibitors (MAOIs; e.g., moclobemide, phenelzine, rasagiline, selegiline, tranylcypromine)
  • nitroglycerin
  • nonsteroidal anti-inflammatory drugs (NSAIDs; e.g., naproxen, ibuprofen)
  • pentoxyfylline
  • phosphodiesterase 5 inhibitors (e.g., sildenafil, tadalafil, vardenafil)
  • potassium supplements or medications that increase potassium in the blood
  • rituximab
  • selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, duloxetine, fluoxetine, paroxetine, sertraline)
  • sodium phosphates
  • tolvaptan
  • trimethoprim

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.