Pretreatment of exercise-induced asthma in adults with aerosols and pulverized tablets.

Eighteen adult asthmatics took part in a double-blind crossover study comparing the effect on exercise-induced asthma (EIA) of pretreatment with aerosolized 1) disodium cromoglycate (DSCG), 2) ipratropium bromide (IPTB), 3) fenoterol, 4) DSCG + IPTB and 5) saline. EIA was completely blocked by pretreatment with the beta 2-agonist, fenoterol. The protective effect of nebulized DSCG and IPTB given alone could not be distinguished from that of isotonic saline. The combination of DSCG and IPTB reduced the post-exercise bronchoconstriction more than any of the two drugs given separately. Thirteen of the 18 patients went on to a double-blind cross-over study of the effect on EIA of pretreatment with the usually recommended dosages off salbutamol, theophylline and their combination administered as pulverized tablets. Seven patients were withdrawn from this part of the study because of side-effects, and in the remaining six none of the oral pretreatments could be distinguished from placebo, despite serum theophylline concentrations within or above the commonly recommended therapeutical range.