Candesartan

Drug Information: Candesartan

Candesartan is an angiotensin II receptor blocker (ARB) used primarily to treat hypertension (high blood pressure). It works by blocking the action of angiotensin II, a substance in the body that causes blood vessels to narrow. By blocking angiotensin II, candesartan helps blood vessels relax and widen, lowering blood pressure. Candesartan is also used to treat heart failure and may be prescribed to protect the kidneys in patients with diabetes and hypertension. It is available in oral tablet form and is usually taken once daily. Careful monitoring of kidney function and blood pressure is essential during candesartan therapy.

Category

Antihypertensive

Mechanism of Action

Candesartan is an Angiotensin II Receptor Blocker (ARB). Angiotensin II is a potent vasoconstrictor and plays a key role in the renin-angiotensin-aldosterone system (RAAS), which regulates blood pressure and fluid balance. Candesartan selectively blocks the binding of angiotensin II to the AT1 receptor subtype found in many tissues, including vascular smooth muscle and the adrenal gland. By blocking this receptor, Candesartan prevents angiotensin II from causing vasoconstriction, thereby lowering blood pressure. Additionally, blocking the AT1 receptor reduces aldosterone secretion from the adrenal gland. Aldosterone promotes sodium and water retention, so by decreasing aldosterone levels, candesartan helps to reduce blood volume and further lower blood pressure. Unlike ACE inhibitors, ARBs like candesartan do not inhibit the breakdown of bradykinin, which is thought to be the reason why ARBs are less likely to cause cough, a common side effect of ACE inhibitors. The overall effect is vasodilation, reduced blood volume, and decreased blood pressure.

Clinical Uses

Candesartan is primarily used in the treatment of hypertension (high blood pressure). It is effective in lowering blood pressure in patients with essential hypertension. It is also used in the management of heart failure, particularly in patients who cannot tolerate ACE inhibitors due to side effects like cough. Candesartan is often prescribed to reduce the risk of cardiovascular events, such as stroke and heart attack, in patients with hypertension and other cardiovascular risk factors. Additionally, Candesartan may be used to slow the progression of diabetic nephropathy (kidney disease) in patients with type 2 diabetes and hypertension, as it helps protect the kidneys from further damage. It can be used alone or in combination with other antihypertensive medications, such as diuretics or calcium channel blockers, to achieve optimal blood pressure control. Studies have also explored its use in migraine prophylaxis.

Dosage

Adults: The usual starting dose for hypertension is 8 mg orally once daily. The dose may be increased to 16 mg or 32 mg once daily as needed to control blood pressure. For heart failure, the target dose is typically 32 mg once daily, but treatment should be initiated at a lower dose (e.g., 4 mg) and titrated up gradually as tolerated.
Pediatrics: Dosage for children is weight-based and should be determined by a physician. Candesartan is generally not recommended for use in children under 1 year of age. For older children, the starting dose is typically lower and titrated based on response and tolerance.
Route of Administration: Oral. Administer once daily, with or without food.

Indications

Common indications for Candesartan include:

• Hypertension (High Blood Pressure)
• Heart Failure
• Prevention of Cardiovascular Events in High-Risk Patients
• Diabetic Nephropathy (Kidney Disease) – to slow progression

Contraindications

Candesartan is contraindicated in the following situations:

• Hypersensitivity to candesartan or any of the excipients.
• Pregnancy: Candesartan can cause fetal harm or death when administered to a pregnant woman.
• Bilateral Renal Artery Stenosis: Significant narrowing of the arteries supplying both kidneys.
• Concomitant use with aliskiren in patients with diabetes mellitus or renal impairment (GFR < 60 mL/min).

Use with caution in patients with volume depletion (e.g., due to diuretics or diarrhea) as it can lead to hypotension.

FAQ

Q: What is Candesartan used for?
A: Candesartan is primarily used to treat high blood pressure (hypertension) and heart failure. It may also be used to protect the kidneys in patients with diabetes and hypertension.

Q: How does Candesartan work?
A: Candesartan is an angiotensin II receptor blocker (ARB). It works by blocking the action of angiotensin II, a hormone that causes blood vessels to constrict. By blocking angiotensin II, candesartan helps blood vessels relax and widen, lowering blood pressure.

Q: What are the common side effects of Candesartan?
A: Common side effects may include dizziness, lightheadedness, fatigue, and headache. Less common but more serious side effects can include kidney problems, allergic reactions, and high potassium levels.

Q: Can I take Candesartan if I am pregnant?
A: No, Candesartan is contraindicated in pregnancy. It can cause serious harm or death to the developing fetus.

Q: How should I take Candesartan?
A: Candesartan is usually taken once daily, with or without food. Follow your doctor’s instructions carefully.

Q: What should I do if I miss a dose of Candesartan?
A: If you miss a dose, take it as soon as you remember. If it is close to the time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not double the dose to catch up.

Q: Can Candesartan be taken with other medications?
A: Candesartan can interact with other medications, including other blood pressure medications, diuretics, and NSAIDs. Be sure to inform your doctor about all medications you are taking, including over-the-counter drugs and supplements.

Q: Does Candesartan have a generic available?
A: Yes, Candesartan is available as a generic medication.