Inhibition of exercise-induced bronchoconstriction by nebulised sodium cromoglycate in patients with bronchial asthma.

In this double blind study, 10 patients with bronchial asthma underwent exercise challenge on five occasions. The first of these was a control test carried out without prior drug administration; the other tests were preceded by the administration, in random order, of a sodium cromoglycate (SCG) capsule, a placebo capsule, an ampoule of sodium cromoglycate solution, and a placebo ampoule. Comparisons of the largest falls in PEFR after exercise showed statistically significant inhibition of exercise-induced bronchospasm, compared with control, with both SCG inhalation solution (P less than 0.01) and SCG powder (P less than 0.01). SCG powder was more active, but the difference was not significant. A significant difference in protection was found between SCG powder and its placebo (P less than 0.01). SCG inhalation solution was also more effective than its placebo, but the difference did not reach significance, since the latter conferred some protection.