Phencyclidine detection during toxicology testing of a university medical center patient population

The rate of detection of phencyclidine during toxicology testing of a university medical center patient population was studied by retrospective review of the results of 6,870 toxicology panels performed on urine during the period September 1, 1984 to September 1, 1987. The rate was compared with that noted in earlier studies of drug detection at this institution. For the three-year period, 91 panels (1.3%) involving 82 individuals were positive for phencyclidine: men, 49 cases; women, 15 cases; children, 10 cases; and neonates, 8 cases. The typical user was a 25 year old Hispanic or Black man who had ingested phencyclidine alone or in combination with at least one other drug (usually ethanol or cocaine) and who had been admitted to the trauma service. Despite use of the same analytical methodology and increased ordering of toxicology tests during the study period, the frequency of phencyclidine detection decreased during each year of the study (1984-85, 2.3% of 1,280 panels; 1985-86, 1.5% of 1,956 panels; and 1986-87, 0.9% of 3,634 panels). These figures are substantially lower than the 5% rate noted in our study of emergency room patients in 1979. These data suggest that the use of phencyclidine may be decreasing, possibly due to increase in abuse of other drugs such as cocaine and the amphetamines and to the more stringent restrictions placed upon phencyclidine synthesis. About half of the phencyclidine-positive findings occurred in trauma patients, suggesting the particular importance of searching for the drug in this population.