A perspective on the role of cromolyn sodium as an antiasthmatic agent.

The effectiveness of cromolyn sodium versus placebo for the prophylaxis of aqthmatic symptoms was studied by using a double-blind-crossover clinical trial in 20 patients with symptomatic asthma. Eleven patients showed significant improvement in maximum voluntary ventilation, dyspnea index, and maximum mid-expiratory flow rate. Asthma uncomplicated by chronic bronchial infection predominated in this group. The average age was 32 years and the mean residual volume/total lung capacity ratio was 32 percent (SD a 10 percent). Nine patients failed to show significant improvement in the above noted variables and chronic bronchial infection was an important factor in the asthma of all these patients; the average age was 50 years and the mean residual volume/total lung capacity ratio was 54 percent (SD 5 11 percent). Good agreement between subjective assessment and objective pulmonary function measurements was noted in 18 out of 20 cases. Cromolyn sodium appears to be more effective in young asthmatics with a low incidence of bronchial infection and with only mild pulmonary hyperinflation.