VSA, the deliberate inhalation of volatile substances (glue sniffing, inhalant abuse, solvent abuse) to achieve intoxication, has been reported from most parts of the world, mainly among adolescents, individuals who live in remote communities, and those whose occupations provide access to abusable substances. VSA produces dose-related effects similar to those of other hypnosedatives. Small doses can rapidly lead to euphoria and other behavioral disturbances similar to those caused by ethanol (alcohol) and may also induce delusions and hallucinations. Higher doses may produce life-threatening effects such as convulsions and coma. Death may ensue indirectly after inhalation of vomit or from direct cardiac or central nervous system toxicity. Chronic abuse of toluene-containing products and of chlorinated solvents such as 1,1,1-trichloroethane, for example, can produce severe organ damage, especially in the liver, kidneys, and brain. Drunken behavior, unexplained listlessness, anorexia, and moodiness may result from VSA, especially in children and adolescents. The hair, breath, and clothing may smell of solvent, and empty adhesive tubes or other containers, potato crisp bags, cigarette lighter refills, and aerosol spray cans are often found. Toxicological examination of blood and tissue specimens is important in confirming a diagnosis of sudden VSA-related death. The development and evaluation of strategies for the treatment of chronic abusers and for prevention are major challenges for the future. 2 tables, 4 figures, and 67 references