The decade of the 1980's saw a dramatic increase in the self-reported prevalence of cocaine use. Population estimates from the National Institute on Drug Abuse National Household Survey indicate that in 1990, 6.2 million Americans had used cocaine during the prior year, 662,000 used cocaine at least weekly and 336,000 daily. The experience of clinicians, emergency rooms, and medical examiners as well as dramatic accounts in the mass media indicate that the use of cocaine carries serious health risks. One reason for the increasing morbidity and mortality associated with cocaine may be a shift in the preferred route of administration. The previously favored route of administration, intranasal "snorting" has been supplanted to a great extent by crack smoking and "freebasing." Given the magnitude of the health problems caused by cocaine, it is prudent to review closely the pathophysiological effects of the drug on major organ systems and identify needed areas for further research. The papers summarized in this editorial discuss the physiological and physiopathological effects on the cardiovascular system, sleep and mood, neuropsychiatric system, and respiratory system. 35 references