PROTECTIVE EFFECT OF INHALED LYSINE ACETYLSALICYLATE ON ALLERGEN-INDUCED EARLY AND LATE ASTHMATIC REACTIONS

Conflicting results have been reported on the effect of nonsteroidal a ntiinflammatory drugs on allergen-induced asthmatic responses. The aim of this study was to investigate the effect of inhaled lysine acetyls alicylate (LASA) on the early and late allergen-induced responses. We studied 16 patients with mild, stable asthma who had an early asthmati c response and 10 patients with a dual (early and late) response. Each patient underwent two challenges with a single dose of allergen asses sed in a preliminary test, after inhalation of either 720 mg of LASA i n 4 ml of saline solution or placebo, according to a randomized, doubl e-blind protocol. Allergen-induced hyperreactivity to methacholine was measured in six patients from each of the early and the dual response groups 2 hours and 24 hours after the challenge, respectively. In the patients with early response, the maximum fall in FEV1 after challeng e was 24% +/- 1% after inhalation of placebo and 14% +/- 2% after inha lation of LASA (p < 0.005). No protection was observed in four patient s who received the drug orally instead of by inhalation. In the patien ts with a dual response, the maximum FEV1 decrease during the early re sponse was 27% +/- 2% after placebo and 21% +/- 2% after LASA (p < 0.0 25). During the late response (between 3 and 8 hours), the maximum dec rease in FEV1 was 28% +/- 4% after placebo and 16% +/- 4% after LASA ( p < 0.005). In both groups allergen challenge caused a significant red uction in methacholine PD20 after treatment with placebo but not with LASA. Without allergen challenge, LASA had no effect on methacholine r eactivity. We conclude that inhaled LASA significantly reduces both th e early and the late asthmatic response to allergen challenge and that it prevents the allergen-induced airway hyperresponsiveness that foll ows these responses.