Candesartan

High blood pressure affects a significant proportion of adults across the United Kingdom and, when left unmanaged, substantially increases the risk of stroke, heart attack, and kidney disease. Candesartan tablets are a prescription medicine used to treat hypertension in adults and to manage heart failure with reduced left ventricular function. Candesartan belongs to a class of medicines called angiotensin receptor blockers, or ARBs, and works by relaxing blood vessels to reduce blood pressure and ease the workload on the heart. It is available in a range of strengths to allow careful dose titration. A prescription can only be issued following a clinical consultation with a registered prescriber.

Candesartan tablets are an oral prescription medicine containing candesartan cilexetil as the active ingredient. Candesartan belongs to the angiotensin II receptor blocker (ARB) class of antihypertensive medicines. ARBs are a widely prescribed group of medicines used in the management of high blood pressure, heart failure, and kidney protection in patients with diabetes and proteinuria.

Candesartan is licensed in the United Kingdom for two indications: the treatment of hypertension (high blood pressure) in adults and the treatment of heart failure with reduced left ventricular systolic function in adults where ACE inhibitors are not tolerated. It is available in five strengths: 2mg, 4mg, 8mg, 16mg, and 32mg tablets. The range of strengths supports careful dose titration, particularly in heart failure, where treatment is initiated at a low dose and increased gradually under clinical supervision.

All clinical information on this page is drawn from the current UK Summary of Product Characteristics for candesartan cilexetil tablets.

Note: Candesartan must not be used during pregnancy. ARBs can cause serious harm to the developing foetus, particularly during the second and third trimesters. If you become pregnant while taking candesartan, contact your prescriber immediately. Women of childbearing potential should use effective contraception during treatment.

Candesartan works by blocking the action of a hormone called angiotensin II at its AT1 receptor. Angiotensin II is a powerful natural substance that causes blood vessels to narrow and stimulates the release of aldosterone, a hormone that promotes sodium and water retention. By blocking the receptor at which angiotensin II acts, candesartan prevents these effects.

Effect on Blood Pressure

With the AT1 receptor blocked, blood vessels relax and widen. This reduces the resistance against which the heart must pump, lowering both systolic and diastolic blood pressure. The antihypertensive effect of candesartan is sustained over 24 hours with once-daily dosing, providing consistent blood pressure control throughout the day and night. Candesartan is used alone or as part of a combination antihypertensive regimen, commonly alongside a calcium channel blocker or a diuretic.

Effect on Heart Failure

In heart failure with reduced left ventricular function, the renin-angiotensin-aldosterone system is overactivated, which contributes to progressive deterioration of cardiac function. By blocking the AT1 receptor, candesartan reduces the harmful effects of this overactivation. It lowers the pressure the heart must work against, reduces fluid retention, and has been shown in clinical trials to reduce cardiovascular mortality and hospitalisation for heart failure. In this indication, candesartan is used as an alternative in patients who cannot tolerate ACE inhibitors or as an addition to ACE inhibitor therapy in selected patients under specialist supervision.

Comparison with ACE Inhibitors

Both ARBs such as candesartan and ACE inhibitors lower blood pressure through the renin-angiotensin-aldosterone system, but by different mechanisms. ACE inhibitors prevent angiotensin II from being formed. ARBs block the receptor at which angiotensin II acts. A key practical difference is that ACE inhibitors commonly cause a persistent dry cough as a side effect, while ARBs are much less likely to do so. Candesartan is therefore a commonly prescribed alternative for patients who develop an ACE inhibitor-related cough.

Always take candesartan exactly as your prescriber instructs. The information below summarises key points from the current UK SmPC. Read the Patient Information Leaflet supplied with your medicine before starting treatment.

• Take candesartan once daily, at the same time each day. Consistent timing helps maintain a steady level of the medicine in your body.
• Candesartan can be taken with or without food.
• Swallow the tablet whole with a glass of water.
• If you miss a dose, take it as soon as you remember on the same day. If you only remember the following day, skip the missed dose and continue with your normal schedule. Do not take two doses on the same day.
• Do not stop taking candesartan without speaking to your prescriber first. Stopping a blood pressure or heart failure medicine suddenly may cause your condition to worsen.

Candesartan tablets are available in five strengths through this service. The appropriate dose will be determined by your prescriber based on the condition being treated, your blood pressure readings, kidney function, potassium levels, and clinical response.

Candesartan 2mg Tablets

The 2mg tablet is used as a starting dose in heart failure, where candesartan must be initiated at a very low dose and increased gradually under close clinical supervision. This strength may also be used in patients who are particularly sensitive to the blood pressure-lowering effects of ARBs, such as those with volume depletion or severe kidney impairment. This strength is not typically used as a starting dose for hypertension in most adults.

Candesartan 4mg Tablets

The 4mg tablet is an early titration step used primarily in heart failure dose escalation. It may also be used for patients requiring a lower starting or maintenance dose for hypertension in specific clinical circumstances, as determined by their prescriber.

Candesartan 8mg Tablets

The 8mg tablet is the standard starting dose for hypertension in adults. For most patients with high blood pressure, treatment begins at 8mg once daily. This dose provides clinically meaningful blood pressure reduction in many patients and allows response to be assessed before any increase is considered.

Candesartan 16mg Tablets

The 16mg tablet is a commonly used maintenance dose for hypertension. If blood pressure is not adequately controlled on 8mg, the dose may be increased to 16mg once daily. For heart failure, 16mg is an intermediate titration target. Your prescriber will advise on the appropriate dose for your circumstances.

Candesartan 32mg Tablets

The 32mg tablet is the maximum recommended dose for hypertension. It is used when lower doses do not provide sufficient blood pressure control. For heart failure, the target dose is 32mg once daily, achieved through gradual titration over several weeks. All dose adjustments are made by your prescriber. Do not increase your dose without medical advice.

Like all medicines, candesartan can cause side effects, although not everyone experiences them. The information below is based on the current UK SmPC. Refer to the Patient Information Leaflet for the full list.

Common Side Effects (may affect up to 1 in 10 people)

• Dizziness or lightheadedness, particularly when standing up quickly (postural hypotension), especially at the start of treatment or after a dose increase.
• Headache.
• Respiratory tract infections such as cough or upper respiratory symptoms. Unlike ACE inhibitors, candesartan is much less likely to cause a persistent dry cough.
• Back pain or joint pain.

Uncommon Side Effects (may affect up to 1 in 100 people)

• Raised blood potassium levels (hyperkalaemia), particularly in patients with kidney impairment or those taking potassium-sparing diuretics or potassium supplements.
• Impaired kidney function, particularly in patients with pre-existing kidney disease or renal artery stenosis.
• Low blood pressure (hypotension), particularly following the first dose in patients who are volume-depleted or taking diuretics.
• Nausea or stomach discomfort.

Serious Side Effects: Seek Urgent Medical Attention

Contact your prescriber or go to your nearest accident and emergency department promptly if you experience any of the following:

• Angioedema - sudden swelling of the face, lips, tongue, throat, hands, or feet. This is a rare but serious reaction that requires immediate medical attention. Although less common with ARBs than with ACE inhibitors, angioedema can still occur with candesartan.
• Signs of significant kidney deterioration such as a marked reduction in urine output or significant swelling.
• Symptoms of very high potassium levels such as muscle weakness, an irregular heartbeat, or tingling and numbness.
• Signs of a serious allergic reaction such as difficulty breathing or a severe skin reaction.

Report any suspected side effect to your prescriber or pharmacist or via the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk.

Candesartan Tablets May Be Suitable If You:

• Are an adult with hypertension who requires antihypertensive treatment, including as an alternative to an ACE inhibitor if you have developed an ACE inhibitor-related cough.
• Have heart failure with reduced left ventricular systolic function and cannot tolerate an ACE inhibitor or are receiving candesartan as an addition to ACE inhibitor therapy under specialist supervision.
• Are already prescribed candesartan and require a repeat prescription through an online prescribing service.

Candesartan Tablets Are Not Suitable If You:

• Are pregnant or planning to become pregnant - candesartan must not be used during pregnancy.
• Have severe liver impairment or cholestasis.
• Are taking aliskiren alongside candesartan if you have diabetes or kidney impairment (eGFR below 60 ml/min/1.73m2).
• Have a known allergy or hypersensitivity to candesartan cilexetil or any excipient listed in the SmPC.
• Are under 18 years of age (this service is for adults only).

Cautions

Particular caution is required in patients with kidney impairment, as candesartan can affect kidney function, particularly in patients with renal artery stenosis or those taking NSAIDs. Patients with a history of ACE inhibitor-induced angioedema should inform their prescriber, as angioedema is possible with ARBs too, though less common. Caution is required in patients who are volume-depleted (such as those taking high-dose diuretics), as the first dose may cause a significant fall in blood pressure. Kidney function and potassium levels should be monitored at the start of treatment and periodically thereafter.

Important Drug Interactions

Candesartan can interact with a number of commonly prescribed medicines. Tell your prescriber about all medicines you take, including over-the-counter products and herbal supplements. The following interactions are of particular clinical importance:

• Potassium-sparing diuretics (such as spironolactone, amiloride), potassium supplements, or salt substitutes containing potassium: combining these with candesartan significantly increases the risk of raised blood potassium (hyperkalaemia).
• ACE inhibitors: combining candesartan with an ACE inhibitor increases the risk of hypotension, hyperkalaemia, and kidney impairment. This combination should only be used under specialist supervision in heart failure patients.
• Aliskiren: the combination of candesartan with aliskiren is contraindicated in patients with diabetes or kidney impairment and is not recommended in other patients.
• NSAIDs such as ibuprofen: these can reduce the antihypertensive effect of candesartan and increase the risk of kidney problems, including acute kidney injury.
• Lithium: candesartan can increase lithium levels, raising the risk of lithium toxicity. Close monitoring is required.
• Other antihypertensive medicines: the blood pressure-lowering effect of candesartan may be enhanced when combined with other antihypertensive agents.

This is not a complete list of interactions. Your prescriber will carry out a full clinical assessment, including a review of your current medicines, before any prescription is considered.

Candesartan is a prescription-only medicine. The clinical consultation is the essential first step. A prescription will only be issued if a registered prescriber determines, based on their individual assessment of your circumstances, that candesartan is clinically appropriate for you.

During your online consultation with Pharmacy Planet, a registered prescriber will review your clinical information. This includes your blood pressure readings or cardiac history, kidney function, potassium levels, current medicines, and relevant medical history, including any previous ARB or ACE inhibitor use. Where you are seeking a repeat prescription, the prescriber will also assess whether your current treatment remains appropriate.

Not all consultations will result in a prescription being issued. The prescriber may recommend a different dose, a different medicine, or suggest that a face-to-face appointment with your GP or specialist is more appropriate. This process is designed to ensure your safety.

If you are already being managed for hypertension or heart failure by your GP or a hospital team, please keep them informed of all medicines you are taking, including any prescribed through online services.

• Store below 30°C.
• Store in the original packaging to protect from light and moisture.
• Keep out of the sight and reach of children.
• Do not use after the expiry date printed on the packaging.
• Do not dispose of medicines via household waste or wastewater. Return unused or out-of-date tablets to your pharmacist for safe disposal.

Full storage instructions are provided in the Patient Information Leaflet supplied with your medicine.

The table below compares ARB tablets and Rasilez (aliskiren), the only direct renin inhibitor licensed for hypertension in the UK. All act on the renin-angiotensin-aldosterone system (RAAS) and are taken once daily as tablets.

Important: This comparison is for general information only and does not replace medical advice. A prescriber will decide which treatment is suitable for you following an online consultation.

Pharmacy Planet is a GPhC-registered pharmacy providing prescription medicines through a clinically led consultation process. Our registered prescribers and pharmacists are committed to patient safety, responsible prescribing, and accurate patient information.

Our pharmacy team is available to answer questions about candesartan, ARB therapy, or cardiovascular health more broadly. We are committed to providing clear, honest information to support you in managing your health safely and with confidence.

References

1. Electronic Medicines Compendium (eMC). Candesartan Cilexetil Tablets — Summary of Product Characteristics. https://www.medicines.org.uk/emc. Accessed August 2026.
2. National Institute for Health and Care Excellence (NICE). Hypertension in adults: diagnosis and management. NICE guideline NG136. https://www.nice.org.uk/guidance/ng136. Accessed August 2026.
3. National Institute for Health and Care Excellence (NICE). Chronic heart failure in adults: diagnosis and management. NICE guideline NG106. https://www.nice.org.uk/guidance/ng106. Accessed August 2026.
4. NHS. Candesartan. https://www.nhs.uk/medicines/candesartan. Accessed August 2026.
5. Joint Formulary Committee. British National Formulary (BNF). Candesartan cilexetil. BMJ Group and Pharmaceutical Press. https://bnf.nice.org.uk. Accessed August 2026.
6. Medicines and Healthcare products Regulatory Agency (MHRA). Yellow Card — report a side effect. https://yellowcard.mhra.gov.uk. Accessed August 2026.