Development of late asthmatic reactions after allergen or exercise challenge tests

In 10 asthmatic patients with exogenous allergy an immediate type asthmatic reaction was provoked by allergen inhalation and by exercise. No difference in the degree of bronchospasm or in the clinical picture could be detected after the two types of challenge, but only after allergen inhalation was a late asthmatic reaction observed. If the late asthmatic reaction is dependent on a foregoing reaction, this indicates that different mechanisms are responsible for the immediate reaction after allergen challenge and exercise challenge. Another possibility could be that the late asthmatic reaction is an independent and special type of asthma occurring after allergen challenge.