irbesartan hydrochloride: clinical use

Prescribing considerations

• Correct significant volume or sodium depletion before initiation because symptomatic hypotension may occur.
• Use particular caution with renal artery stenosis, renal impairment, substantial proteinuria, heart failure, valve stenosis or obstructive hypertrophic cardiomyopathy.
• Dual renin–angiotensin system blockade is generally not recommended; exceptional use requires specialist supervision and close monitoring.
• Irbesartan may contribute to hypoglycaemia in people receiving glucose-lowering treatment.
• Experience is limited after recent kidney transplantation or in severe hepatic impairment.

Contraindications and cautions

• Hypersensitivity to irbesartan or a product excipient.
• Second or third trimester of pregnancy.
• Concomitant aliskiren in patients with diabetes mellitus or renal impairment meeting the product threshold.

Monitoring

• Assess blood pressure, renal function and serum potassium, with closer monitoring in higher-risk patients.
• Consider serum sodium and volume status where clinically relevant.
• Monitor blood glucose where hypoglycaemia is possible.
• If lithium co-administration is unavoidable, monitor serum lithium closely.

Clinical pharmacology

Irbesartan is an orally active, selective AT1-receptor antagonist that does not require metabolic activation. It is highly protein bound, metabolised mainly through glucuronidation and CYP2C9 oxidation, and eliminated through biliary and renal routes.

Formulation and product differences

• The selected film-coated tablet contains lactose and is essentially sodium-free.
• Crushing or dispersing tablets for adults with swallowing difficulties is off-label and may expose a bitter taste; confirm suitability with a pharmacist.
• Excipients, appearance and packaging can differ between manufacturers.

Tablet

Route: Oral

Strengths: 75 mg, 150 mg, 300 mg