This study examined the safety and efficacy of an escalating dose (100 mg, 200 mg, 400 mg/day) of American ginseng over 6 weeks in a single-center, randomized, double-blind, placebo-controlled, crossover trial with 56 subjects with multiple sclerosis and fatigue. There were no serious adverse events but fatigue on ginseng, as assessed by the Fatigue Severity Scale, was not significantly different from fatigue on placebo.