COMPARISON OF THE SINGLE-DOSE PHARMACOKINETICS AND TOLERABILITY OF MODAFINIL AND DEXTROAMPHETAMINE ADMINISTERED ALONE OR IN COMBINATION IN HEALTHY MALE-VOLUNTEERS

An open-label, randomized, crossover study was performed in healthy ma le volunteers to evaluate the potential pharmacokinetic and pharmacody namic interactions and tolerability of single oral doses of modafinil (200 mg) and dextroamphetamine (10 mg). Blood samples were collected f or determination of plasma levels of modafinil, the acid and sulfone m etabolites of modafinil, and dextroamphetamine at intervals through 48 hours after administration for each treatment. Vital signs (blood pre ssure and pulse rate) were measured through 48 hours, and electrocardi ograms were measured through 24 hours after administration. Pharmacoki netic parameters were determined using noncompartmental methods. The d ata collected in this study of 24 healthy volunteers suggest that conc omitant administration of single oral doses of modafinil and dextroamp hetamine has no clinically significant effects on the pharmacokinetic profile of either agent. Although there was a slightly greater inciden ce of adverse events when modafinil and dextroamphetamine were adminis tered together, the concomitant administration of the two drugs was we ll tolerated.