Hypnosis for exercise-induced asthma

Hypnosis has been used for many years in the treatment of asthma, but studies of its usefulness have been controversial. We assessed the efficacy of hypnosis in attenuating exercise-induced asthma (EIA) in 10 stable asthmatics. The subjects ran on a treadmill while mouth breathing for 6 min on 5 different days. Pulmonary mechanics were measured before and after each challenge. Two control exercise challenges resulted in a reproducible decrease in forced expiratory volume in one second (FEV₁). On 2 other days, saline or cromolyn by nebulization was given in a double-blind manner with the suggestion that these agents would prevent EIA. Hypnosis prior to exercise resulted in a 15.9% decrease in FEV₁ compared with a 31.8% decrease on the control days (p < 0.001). Pretreatment with cromolyn resulted in a 7.6% decrease in FEV₁. We conclude that hypnosis can alter the magnitude of a pathophysiologic process, namely, the bronchospasm after exercise in patients with asthma.