Angiotensin II receptor blockers to reduce blood pressure

For general information about drugs used for blood pressure (BP) reduction, and starting and adjusting drug therapy, see Approach to drug therapy for blood pressure reduction.

Angiotensin II receptor blockers (ARBs) have similar cardioprotective and renoprotective effects to angiotensin converting enzyme inhibitors (ACEIs). They should not be used in patients with bilateral renal artery stenosis.

ARBs are usually well tolerated, but sensitivity to ARBs is more likely in patients taking high-dose diuretics, patients with hyponatraemia or renovascular hypertension, and in older patients. Consider starting at a lower dose or increasing the dosing interval in these patients.

If a patient has experienced angioedema while taking an ACEI, there is a risk of the same potentially serious adverse effect with an ARB; a harm–benefit analysis is required before prescribing.

Monitor patients taking ARB therapy for hypotension, kidney impairment and hyperkalaemia. A small rise in serum creatinine (up to 25%) or serum potassium (within the normal range) can occur when drug therapy is started or doses are increased. This may be transient and should not necessarily prompt dose reduction or cessation of the ARB; consider the clinical context of these changes (eg whether they have occurred in isolation, or if other signs or symptoms are present).

The combination of an ARB or ACEI, a diuretic and an NSAID (including selective cyclo-oxygenase-2 [COX-2] inhibitors)—the ‘triple whammy’—can cause acute kidney injury. Avoid this combination, especially in patients with pre-existing kidney disease or dehydration, and in older patients.

Start ARB therapy with a low to moderate dose and increase slowly as required. Suitable dose ranges for a patient with uncomplicated elevated blood pressure are:

A lower starting dose than the doses listed above is appropriate in some patients, such as older patients and patients with reduced kidney or liver function.