Candesartan

High Blood Pressure (Hypertension)

Candesartan is primarily prescribed to treat high blood pressure in adults and children at least 1 year of age. Managing high blood pressure is important because it helps reduce the risk of serious health complications, such as:

• Heart attacks
• Strokes
• Kidney problems

It may be used alone or in combination with other medications to help reach blood pressure goals.

Heart Failure

In adults, candesartan is used to treat heart failure, a condition where the heart muscle is too weak to pump blood effectively to the rest of the body. For these patients, the medication is used to:

• Reduce the risk of death from heart disease.
• Decrease the likelihood of needing to stay in the hospital for heart failure symptoms.

Mechanism of Action

Candesartan works by blocking the action of a natural substance in the body called angiotensin II. This substance is a hormone that causes the muscles in the walls of the blood vessels to tighten and narrow.

When blood vessels are narrow, the heart must work harder to pump blood through the body, which increases blood pressure. Candesartan prevents angiotensin II from binding to its receptors, which leads to several effects:

• Blood vessel relaxation: The blood vessels relax and widen, allowing blood to flow more freely.
• Lower blood pressure: As the vessels widen, the pressure within the circulatory system decreases.
• Reduced heart strain: With lower pressure and wider vessels, the heart does not have to pump as hard to move blood throughout the body.

By improving blood flow and reducing the workload on the heart, this medication helps manage high blood pressure and certain types of heart failure.

Common Side Effects

Many people using candesartan do not experience serious side effects. Common symptoms may include:

• Dizziness or lightheadedness
• Back pain
• Headache
• Sore throat, runny nose, or sneezing
• Stomach pain or diarrhea
• Fatigue or unusual tiredness

Serious Side Effects

Seek medical attention immediately if you experience any of the following serious symptoms:

• Signs of an allergic reaction, including swelling of the face, lips, tongue, or throat
• Difficulty breathing or swallowing
• Fainting
• Hoarseness
• Changes in the amount or frequency of urination
• Muscle weakness or a slow, irregular heartbeat, which may indicate high potassium levels

Fetal Toxicity

Candesartan can cause injury and even death to an unborn baby. This medication should be discontinued as soon as pregnancy is detected. Exposure to drugs that act on the renin-angiotensin system during the second and third trimesters can lead to reduced fetal kidney function and other serious complications for the fetus or newborn.

Low Blood Pressure (Hypotension)

Excessive low blood pressure may occur, especially in patients who are salt- or volume-depleted. This includes individuals taking high doses of diuretics, those on a low-salt diet, or those undergoing dialysis. Blood pressure should be monitored closely when starting treatment or adjusting the dose.

Kidney Function and Electrolytes

Changes in kidney function, including acute renal failure, may occur in certain patients. Those with severe heart failure or renal artery stenosis may be at increased risk. Additionally, candesartan can cause hyperkalemia (high blood potassium levels). Monitoring of serum creatinine and potassium levels is typically required, particularly for patients with heart failure or chronic kidney disease.

Drug Interactions and Contraindications

• Dual Blockade: Combining candesartan with other drugs that block the renin-angiotensin system, such as ACE inhibitors or aliskiren, increases the risk of kidney impairment, low blood pressure, and high potassium.
• Diabetes: Candesartan must not be used in combination with aliskiren in patients with diabetes.
• Hypersensitivity: This medication is contraindicated in individuals with a known hypersensitivity to candesartan or any of its ingredients.

Pregnancy

Candesartan carries a boxed warning regarding its use during pregnancy. Taking this medication during the second and third trimesters can cause serious injury or death to a developing fetus. Potential risks to the baby include low blood pressure, kidney failure, skull deformities, and problems with lung development.

If you become pregnant while taking candesartan, you should contact your healthcare provider immediately. The medication is typically stopped as soon as pregnancy is confirmed to minimize risks to the fetus. Discuss alternative treatments for blood pressure or heart failure with your doctor if you are planning to become pregnant.

Breastfeeding

It is currently unknown whether candesartan passes into human breast milk. Because of the potential for serious side effects in a nursing infant, healthcare providers generally recommend either stopping the medication or stopping breastfeeding.

If you are breastfeeding or planning to breastfeed, discuss the risks and benefits with your doctor to determine the safest course of treatment for your condition.

Available Forms

Candesartan is available as an oral tablet. It is intended to be swallowed whole and is taken as directed by a healthcare provider.

In addition to the single-ingredient version, candesartan is also available in combination tablets that include other active ingredients, such as diuretics, to assist in blood pressure control.

FDA Approval and Indications

Candesartan was initially approved by the U.S. Food and Drug Administration (FDA) for the treatment of hypertension (high blood pressure) in adults. Its approved indications include:

• Hypertension in adults and pediatric patients ages 1 to less than 17 years.
• Heart failure (NYHA Class II-IV) in adults with left ventricular systolic dysfunction to reduce the risk of cardiovascular death and hospitalization.

Boxed Warning

The FDA has issued a boxed warning for candesartan regarding fetal toxicity. Medications that act directly on the renin-angiotensin system can cause injury and death to a developing fetus if used during pregnancy. Patients are advised to discontinue the medication as soon as pregnancy is detected.

Safety Communications and Contraindications

The FDA has issued safety communications regarding the dual blockade of the renin-angiotensin system. Using candesartan in combination with aliskiren is contraindicated in patients with diabetes. This combination increases the risk of severe side effects, including:

• Hypotension (dangerously low blood pressure)
• Hyperkalemia (high potassium levels)
• Changes in kidney function, including acute renal failure

Regulatory guidelines also suggest caution when combining candesartan with ACE inhibitors in patients with heart failure, as this may increase the risk of adverse reactions.

Importance of Continuous Use

Candesartan helps control high blood pressure and heart failure but does not cure these conditions. It is essential to keep taking the medication exactly as prescribed, even if you feel healthy. Most people with high blood pressure do not feel sick, and stopping the medication can lead to a return of high blood pressure levels.

Risks of Abrupt Cessation

Stopping candesartan suddenly may cause your blood pressure to increase rapidly. This can increase the risk of serious cardiovascular events. If you must stop taking this medication, your healthcare provider will determine the safest way to do so, which may involve a gradual reduction in dosage.

Medical Supervision

Always talk to a healthcare professional before making any changes to your treatment plan. They can provide guidance on how to safely transition off the medication if it is no longer appropriate for your condition. Do not skip doses or stop the medication because you feel better, as consistent levels of the drug are necessary to manage your condition effectively.