Elimination of ephedrines in urine following multiple dosing: the consequences for athletes, in relation to doping control.

To study the elimination of ephedrines with reference to the International Olympic Committee (IOC) doping control cut-off levels, following multiple dosing of over-the-counter decongestant preparations. A double-blind study was performed in which 16 healthy male volunteers were administered either pseudoephedrine or phenylpropanolamine in maximal recommended therapeutic doses over a 36-h period. Urine was collected every two hours between 08:00 and 24:00 h and at 04:00 h throughout the testing period of three days. Urine drug levels were quantified using high performance liquid chromatography. Side-effects were assessed, including heart rate and blood pressure, every four hours between 08:00 and 20:00 h. Mean (95% CI) total phenylpropanolamine and pseudoephedrine eliminated unchanged was 75 (88, 61) and 81 (92, 71)%, respectively. Maximum urine concentrations of phenylpropanolamine and pseudoephedrine were 112.1 (164.2, 59.9) and 148.5 (215.0, 82.1) mg.l(-1), respectively. A peak in drug urine concentration occurred four hours following the final dose. There were no adverse cardiovascular effects and only mild CNS stimulation was evident. Following therapeutic, multiple dosing, drug levels remain above the IOC cut-off levels for a minimum of 6 h and 16 h following final doses of phenylpropanolamine and pseudoephedrine, respectively. Athletes require informed advice on this from their healthcare professionals.