Psychological and physiological effects of bupropion compared to methylphenidate after prolonged administration in healthy volunteers (NCT00285155)

Bupropion is largely used as an antidepressant and smoking cessation therapy. The aim of this work was to compare pharmacodynamic properties of bupropion and the amphetamine-like methylphenidate after sustained administration in humans. Twelve male volunteers completed this randomized, double-blind, placebo controlled, cross-over study. Bupropion and methylphenidate were administered separately for initial half-dose 6-day periods (150 and 10 mg respectively) followed by full-dose 8-day periods (300 and 20 mg respectively). Outcomes were subjective feelings, cognitive performances, autonomic and physiological parameters. Data are expressed as mean(SEM). After repeated administration, bupropion, like methylphenidate, decreased asthenia-fatigue [44(3.2) and 42(3.7), respectively vs. 53(4.1) for placebo; p = 0.034], despite an impairment of sleep onset [-4.3(3.32) and -1.9(3.76), respectively vs. +7.5(3.69); p = 0.016]. Both drugs increased resting diastolic blood pressure [67.9(1.23) and 65.7(0.98), respectively vs. 62.5(1.42) mm Hg; p = 0.001], body temperature [36.5(0.12) and 36.5(0.14) vs. 36.3(0.10) A degrees C; p = 0.037] and decreased body weight [-0.7(0.23) and -0.6(0.22), respectively vs. +0.2(0.27) kg; p = 0.038]. No significant change could be observed on cognitive functions, appetite and energy consumption. Although it may not share all the properties of stimulant drugs, the effect profile of bupropion presents a number of similarities with that of methylphenidate over a 2-week treatment period.