Candesartan

What is Candesartan?

Candesartan is a prescription medication that belongs to a class of drugs called angiotensin receptor blockers (ARBs). It is primarily used to treat high blood pressure (hypertension) and heart failure by blocking the action of angiotensin II, a hormone that causes blood vessels to narrow. This medication helps relax blood vessels, allowing blood to flow more easily and reducing the workload on the heart.

Uses

Candesartan is approved for several cardiovascular conditions:

• Hypertension: The most common use, helping to lower blood pressure and reduce the risk of stroke, heart attack, and kidney problems
• Heart failure: Used in patients with reduced ejection fraction to improve symptoms and reduce hospitalizations
• Diabetic nephropathy: Helps protect kidney function in diabetic patients with protein in their urine
• Post-heart attack protection: May be prescribed to reduce cardiovascular events in high-risk patients
• Migraine prevention: Sometimes used off-label to reduce the frequency of migraine headaches

How it works

Candesartan works by selectively blocking angiotensin II type 1 (AT1) receptors in blood vessels and other tissues. When angiotensin II cannot bind to these receptors, it cannot cause blood vessels to constrict or trigger the release of aldosterone, a hormone that increases sodium and water retention. This dual action results in vasodilation (widening of blood vessels) and reduced fluid retention, ultimately lowering blood pressure and decreasing the heart’s workload.

Side effects

Common side effects include:

Submit Your Paper

• Dizziness or lightheadedness
• Headache
• Fatigue or weakness
• Upper respiratory tract infections
• Back pain
• Nausea
• Diarrhea
• Runny or stuffy nose

Serious side effects that require immediate medical attention:

• Severe drop in blood pressure (hypotension)
• Kidney problems or kidney failure
• High potassium levels (hyperkalemia)
• Severe allergic reactions with swelling of face, lips, or throat
• Chest pain or irregular heartbeat

Warnings and precautions

• Pregnancy: Candesartan is contraindicated during pregnancy as it can cause serious harm or death to the developing fetus, particularly during the second and third trimesters
• Kidney disease: Patients with severe kidney impairment or those on dialysis should use this medication with extreme caution and require dose adjustments
• Liver disease: Those with hepatic impairment may need lower starting doses due to reduced drug clearance
• Dehydration: Patients who are volume-depleted or dehydrated are at higher risk for excessive blood pressure reduction
• Elderly patients: May be more sensitive to blood pressure-lowering effects and require careful monitoring

Interactions

• ACE inhibitors: Combination increases risk of kidney problems and high potassium levels
• Potassium supplements and salt substitutes: Can lead to dangerous elevations in blood potassium levels
• NSAIDs (ibuprofen, naproxen): May reduce the blood pressure-lowering effect and increase kidney damage risk
• Lithium: Candesartan may increase lithium levels, potentially causing toxicity
• Diuretics: Combined use may cause excessive blood pressure reduction, especially when starting treatment
• Aliskiren: Combination is contraindicated in patients with diabetes or kidney disease
• Potassium-sparing diuretics: Increases risk of hyperkalemia when used together
• Rifampin: May reduce candesartan effectiveness by increasing its metabolism

Check interactions with the GMJ Interaction Checker

Dosage

For hypertension, the typical starting dose is 16 mg once daily, which may be increased to a maximum of 32 mg daily based on blood pressure response. For heart failure, treatment usually begins with 4 mg once daily, gradually increasing to a target dose of 32 mg daily as tolerated. Patients with kidney or liver impairment may require lower starting doses. The medication can be taken with or without food, and it’s important to take it at the same time each day for consistent blood pressure control. Dosage adjustments should always be made under the supervision of a healthcare provider who will monitor blood pressure, kidney function, and potassium levels regularly.

Sources: FDA DailyMed drug labels (public domain), BNF, WHO Essential Medicines List. This article is for informational purposes only and does not constitute medical advice. Always consult your healthcare provider before starting or stopping any medication.

This work is licensed under Creative Commons Attribution 4.0 International (CC BY 4.0). You are free to share and adapt this content with attribution to GMJ News (news.gmj.ge).