Dissociative drug dependência including ketamine or PCP is a transtorno of regulation of dissociative drug uso arising from repeated or continuous uso of dissociative drugs. The characteristic feature is a strong internal drive to uso dissociative drugs, 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 dissociative drugs. The features of dependência are usually evident over a period of at least 12 months but the diagnosis may be made if dissociative drugs uso is continuous (daily or almost daily) for at least 3 months.