ANGIONEUROTIC-EDEMA ATTRIBUTED TO THE USE OF LOSARTAN

Background: Angioedema is a well-known adverse effect of angiotensin-c onverting enzyme inhibitors. The bradykinin accumulation as a result o f the decreased degradation of bradykinin is thought to be the causal mechanism. Angiotensin II antagonists seem to have no effect on the de gradation of bradykinin. Therefore, it was expected that angioedema wo uld not occur during treatment with losartan potassium, the first oral ly active angiotensin II antagonist. Methods: We reviewed the 13 case reports of angioedema associated with the use of losartan reported to Lareb (Netherlands Pharmacovigilance Foundation, Den Bosch) and to the Drug Safety Unit of the Inspectorate for Health Care, Ryswyh, in the Netherlands since the introduction of losartan in 1995 until May 1997. Results: In all 13 cases, a diagnosis of angioedema attributed to the use of losartan seems to be very plausible. In 7 cases the diagnosis could not be confirmed by a physician because the symptoms had already been resolved, but the signs and symptoms clearly indicated angioedem a. The adverse reactions occurred within 24 hours to 16 months after t he initiation of losartan therapy. Three patients had previously exper ienced angioedema during treatment with an angiotensin-converting enzy me inhibitor. Eleven of the patients involved were women and 2 were me n. Conclusions: Our observations strongly suggest that the onset of an gioedema was associated with the use of losartan. Physicians and pharm acists should be aware of this potentially life-threatening complicati on. It may be advisable not to prescribe angiotensin II antagonists to patients with a history of angioedema (of whatever origin).