Gamma-hydroxybutyrate (GHB) originally was investigated as an anesthetic agent during the 1960s but was abandoned because of side effects including myoclonus and emergence delirium. In 2002, it was approved by the FDA as a treatment for cataplexy and in 2005 for excessive daytime sleepiness in patients with narcolepsy. For abuse purposes, GHB is readily available through the illicit drug market and can be made in home laboratories by using recipes posted on the Internet. As a result of increasing abuse, GHB without a legitimate prescription is regulated as a Schedule I substance. Chemical precursors that are converted to GHB in the body, including gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD), are also regulated as Schedule I analogs (when intended for human consumption). These chemicals often are sold under constantly changing product names with intentionally obscure chemical synonyms (Table II–28), and to avoid the legal consequences of selling an analog intended for human consumption, they may be sold as a cleaner, paint stripper, nail polish remover, or solvent, labeled “not for ingestion.”