Ten healthy, female, volunteer athletes attended two treadmill familiarization sessions and were then randomly assigned to either a placebo or pseudoephedrine group under double blind conditions. Each subject was given a graded exercise test (Bruce Protocol), then crossed over and re-tested after one week. All measurements (i.e., heart rate [HR], respiratory exchange ratio [RER], ventilation [VE], oxygen consumption VO2, respiration rate [RR], tidal volume [TV], systolic blood pressure [SBP], diastolic blood pressure [DBP], total exercise time [TET], core temperature [CT] and ratings of perceived exertion [RPE]) were analyzed using a two tailed, paired t-tests (p < or = 0.05). HR at the ends of stages one, two, three and four and also following 8 minutes of recovery were significantly higher on pseudoephedrine when compared to placebo (p < 0.05). No other significant differences were observed at submaximal exercise, maximal exercise or recovery. These data suggest that a recommended dose of 60 mg pseudoephedrine does not enhance or impair VO2 or other selected cardiopulmonary variables during submaximal or maximal exercise, however, it may augment submaximal exercise HR and perhaps slow HR recovery.