Ecard

Irbesartan is a type of medicine known as an angiotensin II receptor antagonist. It works by attaching to AT1 receptors, which blocks the effects of angiotensin II that would otherwise narrow blood vessels and trigger the release of aldosterone.

Irbesartan is contraindicated in the second and third trimesters of pregnancy. In these months, substances that act directly on the renin-angiotensin-system can cause foetal or neonatal renal failure, foetal skull hypoplasia and even foetal death. As a precaution, Irbesartan should preferably not be used in the first trimester either. A woman who is planning a pregnancy should be switched to a suitable alternative treatment beforehand. Once a pregnancy is diagnosed, the medicine should be stopped as soon as possible. When the treatment was taken inadvertently for a long period, the foetal skull and renal function should be checked with echography.

Irbesartan is also contraindicated during lactation. It is not known whether it passes into human milk, but it is excreted in the milk of lactating rats.

Renal impairment: you don't need to adjust the dose of Irbesartan in patients with impaired renal function. For patients on haemodialysis, a lower starting dose of Irbesartan 75 mg should be considered.

Intravascular volume depletion: volume and/or sodium depletion should be corrected before Irbesartan is given.

Hepatic impairment: no dose adjustment is needed in patients with mild to moderate hepatic impairment. There is no clinical experience in patients with severe hepatic impairment.

Hypertensive patients with type 2 diabetes and renal disease: in an analysis from the study in patients with advanced renal disease, the effects of Irbesartan on renal and cardiovascular events were not the same across all subgroups. They appeared less favourable in women and in non-white subjects.

Hyperkalaemia: as with other drugs that affect the renin-angiotensin-aldosterone system, hyperkalaemia may occur during treatment with Irbesartan. This is more likely when there is renal impairment, overt proteinuria due to diabetic renal disease, and/or heart failure. Serum potassium should be monitored closely in patients at risk.

Aortic and mitral valve stenosis, obstructive hypertrophic cardiomyopathy: as with other vasodilators, special caution is needed in patients with aortic or mitral stenosis, or obstructive hypertrophic cardiomyopathy.

Primary aldosteronism: patients with primary aldosteronism generally don't respond to anti-hypertensive drugs that work by inhibiting the renin-angiotensin system. So the use of Irbesartan is not recommended in them.

General: some patients depend mainly on the renin-angiotensin-aldosterone system for their vascular tone and renal function (for example, patients with severe congestive heart failure or underlying renal disease, including renal artery stenosis). In these patients, treatment with angiotensin converting enzyme inhibitors or angiotensin-II receptor antagonists, which affect this system, has been linked with acute hypotension, azotaemia, oliguria, or rarely acute renal failure. As with any anti-hypertensive agent, an excessive fall in blood pressure in patients with ischaemic cardiopathy or ischaemic cardiovascular disease could result in a myocardial infarction or stroke.

Adults who took Irbesartan at doses of up to 900 mg/day for 8 weeks showed no toxicity. If an overdose does happen, low blood pressure (hypotension) and a fast heart rate (tachycardia) are the most likely effects. A slow heart rate (bradycardia) might also occur.

There is no specific information on how to treat an Irbesartan overdose. The patient should be watched closely, and treatment should be symptomatic and supportive. Suggested measures include inducing vomiting and/or gastric lavage. Activated charcoal may also help. Irbesartan is not removed by haemodialysis.

Keep Irbesartan in a cool, dry place and away from light.