Hallucinogen dependência is a transtorno of regulation of hallucinogen uso arising from repeated or continuous uso of hallucinogens. The characteristic feature is a strong internal drive to uso hallucinogens, which is manifested by impaired ability to control uso, increasing priority given to uso over other activities and persistence of uso despite harm or negative consequences. These experiences are often accompanied by a subjective sensation of urge or craving to uso hallucinogens. The features of dependência are usually evident over a period of at least 12 months but the diagnosis may be made if hallucinogens uso is continuous (daily or almost daily) for at least 3 months.