No abstract

The relative effectiveness of ephedrine, theophylline, hydroxyzine, and their combinations in relieving cycloergometer exercise-induced asthma were studied in 16 children and adolescents. Ephedrine had no effect on post-exercise asthma, hydroxyzine had a weak effect on hastening recovery, while theophylline modified the post-exercise response significantly. The three drugs together produced an additive effect superior to that of theophylline alone.

This study was designed to assess the effectiveness of comolyn sodium in modifying exercise-induced bronchospasm (EIB). Twenty children and adolescents with EIB were given either cromolyn or placebo in a prerandomized double-blind fashion. They then performed a free running maneuver. Pulmonary function tests were obtained before and after this exercise. Patients returned one week later to repeat the same procedure. This time subjects took placebo if they had previously taken cromolyn and vice versa. Significant beneficial effects of cromolyn were noted in forced vital capacity and forced expiratory volume in one second measurements but not in forced expiratory flow between 25% and 75% of the flow-volume curve) (FEF 25%-75%). This suggests that larger airway disease is preferentially helped by cromolyn when subjects are stressed maximally as with a free running system. Subjects who received placebo on study day 1 and cromolyn on study day 2 showed the most striking benefit from cromolyn. This may be related to the better baseline status of subjects on day 2 as well as to familiarity with the procedure and medication.

The free running test has been successfully carried out in patients from 5 to 21 years old. It has the following advantages: (1) it simulates normal exercise pattern; (2) it is readily performed in any health care setting; (3) it is simple to perform and noninvasive in nature; and (4) it reveals a maximum decrease in forced expiratory volume at one second at five minutes after the exercise period. There seems to be a seasonal variation that may alter outcome of tests.