Hydration and urinary pseudoephedrine levels after a simulated team game

This study investigated the influence of dehydration on urinary levels of pseudoephedrine (PSE) after prolonged repeated effort activity. Fourteen trained male athletes performed a simulated team game circuit (STGC) outdoors over 120 min under three different hydration protocols: hydrated (HYD), dehydrated (DHY) and dehydrated + post-exercise fluid bolus (BOL). In all conditions, a 60 mg dose of PSE was administered 30 min before each trial and at half time of the STGC. Urinary PSE levels were measured before drug administration and at 90 min post-exercise. Additionally, body mass (BM) changes and urinary specific gravity (USG), osmolality (OSM), creatinine (Cr) and pH values were recorded. No differences in PSE levels were found 90 min post-exercise between conditions (HYD: 208.5 ± 116.5 μg.ml-1; DHY: 238.9 ± 93.5 μg.ml-1; BOL: 195.6 ± 107.3 μg.ml-1), although large variations were seen within and between participants across conditions (range: 33 to 475 μg.ml-1: ICC r = 0.03-0.16, p>0.05). There were no differences between conditions in USG, OSM, pH or PSE/Cr ratio. The %BM lost due to exercise had no association with post-recovery PSE concentrations (p>0.05; r = 0.156-0.396) in any condition. In conclusion, hydration status did not influence urinary PSE levels after prolonged repeated effort activity, with ~70% of samples greater than the WADA limit (>150 μg.ml-1) and ~30% under. Due to the unpredictability of urinary PSE values, athletes should avoid taking any medications containing PSE during competition.