Effects of salbutamol, ipratropium bromide and disodium cromoglycate on breathlessness induced by exercise in normal subjects.

1 Healthy volunteers undertook submaximal graded exercise while objective measurements of cardio-respiratory function were made and breathlessness was assessed with serial visual analogue scales. 2 A useful and consistent relationship existed between breathlessness and ventilation for individual subjects. 3 Drugs were examined in this system to test whether they modified the relationship between ventilation and breathlessness such that less breathlessness occurred for a given level of ventilation. 4 Salbutamol, ipratropium bromide and disodium cromoglycate given by inhalation did not reduce breathlessness in healthy subjects during exercise.