Depersonalization (DP) is a common but little-studied phenomenon. Persistent DP may occur as a primary disorder or in a range of neuropsychiatric contexts, such as schizophrenia and temporal lobe epilepsy. It occurs commonly with derealization (DR); this DP-DR symptom complex is characterized by a feeling of detachment from one’s surroundings (DR), and one’s own emotions, sensory perceptions, and sense of self (DP), such that both self and environment take on a disturbing air of unreality. Transient DP-DR is often seen in fatigue, in the face of extreme danger, and during or following intoxication with alcohol and/or drugs; some sufferers from chronic DP attribute the onset to a specific episode of illicit drug use. The purpose of this study was examine the characteristics and symptomatology of a group of DP-DR sufferers following drug use and compare them with the findings from a group of DP-DR sufferers with no history of drug abuse. The researchers analyzed cases drawn from the database of referrals to the depersonalization clinic and research unit affiliated with a psychiatric hospital and research center. Participants were 164 individuals with chronic DP symptoms; 40 of these cases indicated the onset of symptoms to an episode of illicit drug use. A wide range of demographic and clinical variables was measured using questionnaires and standardized rating scales. Findings from the study show that individuals in the drug-induced DP group were significantly younger and had a much larger proportion of males compared to the non-drug group. Certain clinical and phenomenological differences were found between these groups, but in general the groups were strikingly similar. This finding was reinforced by the fact that when the drug-induced group was compared with an age and sex-matched subset of the non-drug group, the differences between the groups largely disappeared. The researchers conclude that drug-induced DP does not appear to represent a distinct clinical syndrome. The neurocognitive mechanisms of the genesis and maintenance of DP are likely to be similar across clinical groups, regardless of precipitants. Study limitations are discussed. 1 table and 26 references