Sodium Cromoglycate Bp in the Prevention of Exercise–induced Asthma

Twenty-two asthmatics and 10 control subjects undertook standardized submaximal exercise on two ergometers, the treadmill and the bicycle to study the effect of sodium cromoglycate BP (formerly disodium cromoglycate) (DSCG) taken before exercise on exercise-induced asthma. Utilizing a double-blind crossover technique, the order of exercise testing and administration of DSCG and placebo were randomized. Control subjects exhibited no significant variation in ergometer work-loads or lung volumes after exercise. Inhalation of DSCG 15 minutes before exercise afforded significant protection from exercise-induced asthma in 77·2% of asthmatic subjects. Wide variation of the response after exercise was observed, ranging from complete protection (45·5%) to failure to prevent asthma (22·8%). Exercise-induced asthma which occurred after DSCG inhalation was of shorter duration than that occurring after placebo. Amelioration of exercise-induced asthma by DSCG was noted to be independent of the age of the patient, initial airways resistance and previous exposure to DSCG therapy. DSCG is considered an excellent preexercise agent to assist in normalizing the sporting and physical recreational activities of asthmatics.