Some asthma patients and physicians who treat asthma have reported that stress worsens their disease. It has also recently been shown that chronic stressful life events increase airway inflammation 6-24 h after inhalation of antigen in patients with allergic asthma. However, there is no data regarding the effect of an acute stressor on the airway constriction that occurs within minutes of antigen inhalation (early pulmonary response) in this same population. The aim of this study was to examine this effect in eight females with allergic asthma. Each subject was challenged with increasing concentrations of inhaled allergen on a control visit (no stress) and on a stress visit, when they were asked to verbally recount an emotionally stressful situation between each concentration. Systolic (SP) and diastolic (DP) blood pressure, cardiac frequency (fC) and forced expiratory volume in one second (FEV1) were measured on both visits. SP, DP and fC were statistically increased on the stress visit as compared to control. Per cent decrease in FEV1 at the same last dose of allergen was significantly less on the stress visit (11.2 +/- 7.0%) compared to control (15.0 +/- 8.7%). These findings suggest that the early pulmonary response to inhaled allergen is attenuated while verbally re-experiencing an acute emotional stressor in females with allergic asthma.