Bristol-Myers Squibb has revised several sections of the summary of product characteristics for Aprovel (irbesartan) tablets. The special warnings section on hyperkalaemia has been amended and now reads: "As with other drugs that affect the renin-angiotensin-aldosterone system, hyperkalaemia may occur during the treatment with Aprovel, especially in the presence of renal impairment and/or heart failure. Adequate monitoring of serum potassium in patients at risk is recommended." A paragraph on post- marketing experience has been added to the undesirable effects section. It says that, as with other angiotensin-II receptor antagonists, rare cases of hypersensitivity reactions (rash, urticaria, angioedema) have been reported. Asthenia, diarrhoea, dizziness, dyspepsia, headache, hyperkalaemia, myalgia, nausea and tachycardia have been reported very rarely during post-marketing surveillance. In the pharmacokinetic properties section, the plasma protein binding has been changed from 90 per cent to 96 per cent.