Using historical research that draws on new primary sources, I review the causes and course of the first, mainly iatrogenic amphetamine epidemic in the United States from the 1940s through the 1960s. Retrospective epidemiology indicates that the absolute prevalence of both nonmedical stimulant use and stimulant dependence or abuse have reached nearly the same levels today as at the epidemic's peak around 1969. Further parallels between epidemics past and present, including evidence that consumption of prescribed amphetamines has also reached the same absolute levels today as at the original epidemic's peak, suggest that stricter limits on pharmaceutical stimulants must be considered in any efforts to reduce amphetamine abuse today.