Has cough been reported for irbesartan?/nA patient developed a cough while using an ACE-inhibitor,

Fråga: Has cough been reported for irbesartan?

A patient developed a cough while using an ACE-inhibitor, then he used Aprovel (irbesartan) instead, after 3 weeks of Aprovel (75 mg/day) treatment, he developed a cough again.

Sammanfattning: Irbesartan may cause cough, but seemingly at a lower frequency than observed for ACE inhibitors.

Further studies with adequate controls are needed to compare the true incidence of cough produced by these receptor blockers.

Svar: Irbesartan is the newest member of ARAs (angiotensin II receptor antagonists). The mechanism of action is similar to other ARAs like losartan, and valsartan by blocking the binding of type I receptors of angiotensin II.

Since it is a new drug, the knowledge about its side effects including cough is limited. In one double-blind study, an antihypertensive regimen based on irbesartan had a better tolerability profile with fewer adverse events (55 per cent vs 64 per cent) and significantly less cough (2.5 per cent vs 13.1 per cent, p = 0,007) when compared with the enalapril group (2).

In another study, a total of 200 patients were randomised to irbesartan or enalapril treatment (1). The frequency of overall adverse events was similar in both groups. The incidence of cough in enalapril and irbesartan groups was 17 per cent and 10 per cent, respectively (1).

There are similar results with other ARAs. The incidence of dry coughing was 1.0 per cent and 12.2 per cent as a spontaneously reported discomfort at week 12 in losartan and enalapril groups respectively (3). The frequencies of cough in a selected group of patients using valsatran, lisinopril, or hydrochlorothiazide were 19.5 per cent, 68.9 per cent, and 19.0 per cent, respectively. Hydrochlorothiazide which is well-known not to cause cough was used as a negative control in some studies (4,5). No difference has been observed between the negative control group and the group treated with ARAs.

According to WHO reports, there are 157 cases of cough related to losartan treatment but not any case yet concerning irbesartan. 1 Mimran A, Ruilope L, Kerwin L, Nys M, Owens D, Kasslertaub K, Osbakken M: A randomised, double blind comparison of the angiotensin II receptor antagonist, irbesartan, with the full dose range of enalapril for the treatment of mild to moderate hypertension. J Hum Hypertens 1998; 12: 203-8 (Abstract) 2 Larochelle P, Flack JM, Marbury TC, Sareli P, Krieger EM, Reeves RA: Effects and tolerability at irbesartan versus enalapril in patients with severe hypertension. Irbesartan Multicenter Investigators. Am J Cardiol 1997; 80: 1613-15 (Abstract) 3 Tikkanen I, Omvik P, Jensen H for the Scandinavian study group: Comparison of the angiotensin II antagonist losartan with the angiotensin converting enzyme inhibitor enalapril in patients with essential hypertension. J Hypertens 1995; 13: 1343-51 4 Benz J, Oshrain C, Henry D, Avery C, Chiang YT, Gatlin M: Valsartan, a new angiotensin II receptor antagonist: A double-blind study comparing the incidence of cough with lisinopril and hydrochlorothiazide. J Clin Pharmacol 1997; 37: 101-7 5 Lacourciere Y, Brunner H, Irwin R, Karlberg BE, Ramsay LE, Snavely DB, Dobbins TW, Faison EP, Nelson EB, and Losartan Cough Study Group. Effects of modulators of the renin-angiotensin-aldosterone system on cough. J Hypertens 1994; 12: 1387-93