Inpatient treatment of PCP abusers and users.

Screening of 155 consecutive admissions to a voluntary, 4-6 week substance abuse inpatient rehabilitation program revealed a 13% prevalence of PCP abuse (defined by DSM-III criteria) and a 23% prevalence of nonabusive PCP use. The 20 PCP abusers were significantly younger (31.6 vs 40.2 years) and had more prior arrests (2.0 vs 0.8) than the 36 nonabusive users, but did not differ in other sociodemographic characteristics. The age range of patients was older than previously reported in the literature, with three PCP abusers (15%) and 15 users (42%) 40 years of age or older. A majority of both abusers (80%) and users (97%) also abused other drugs, including alcohol (57%), opiates (29%), marijuana (29%), and stimulants (18%). The mean length of stay for PCP abusers was 27 days, with 11 completing inpatient treatment. Urine samples were collected upon admission from all patients and assayed for PCP by gas chromatography with N-P detection (sensitivity = 0.1 ng/mL). Patients with initial positive PCP results had follow-up urines collected at least weekly until the PCP assay was negative or they left the treatment program. Twenty-seven percent of patients had PCP detected in admission urine samples, one-third of whom initially denied PCP use. Six patients still had PCP detected after 4 weeks of hospitalization, without evidence of PCP reuse. These findings suggest that PCP abuse and use are common among unselected patients seeking substance abuse inpatient treatment and that they are not confined to the adolescent/young adult age group.