Blunting of TSH response to TRH in chronic cocaine and phencyclidine abusers.

The TRH stimulation test was administered to 10 cocaine and 10 phencyclidine abusers as well as to 10 controls. No subjects had clinical evidence of depression. Significantly more blunting of the response of TSH to TRH was shown in cocaine and phencyclidine abusers compared with that seen in controls. No significant differences in blunting of response were seen between the cocaine and phencyclidine groups.

Phencyclidine in CSF and serum: a case of attempted filicide by a mother without a history of substance abuse.

A previously healthy 30-year-old black woman with no history of substance abuse was hospitalized after she attempted to drown her 4-year-old son. She had become progressively confused and delusional after a flu-like illness 2 weeks before. Serum and lumbar CSF samples assayed for phencyclidine (PCP) by gas chromatography-mass spectrometry with d5 PCP as an internal standard were positive. The patient recovered rapidly after treatment with haloperidol and acidification of her urine. Suspicion of PCP abuse should remain high among patients with psychosis, even for those with no history of substance abuse.

Chronic phencyclidine abuse and physical assault.

When the authors investigated aggressive behavior on a phencyclidine (PCP) detoxification and rehabilitation unit and compared similar types of behavior on a heroin unit, they found no differences between the two units. The urinary PCP levels of a subgroup of 75 patients admitted to the PCP unit who had PCP-positive urine were significantly higher than those of 75 patients admitted to an acute psychiatric ward because of violent behavior who also had PCP-positive urine. The authors discuss the implications of these findings and the need for more information on the relationship between PCP levels in blood and urine and behavior.

Radioimmunoassay for phencyclidine (PCP) in serum.

This accurate, sensitive radioimmunoassay for determining phencyclidine concentrations in serum specimens involves the use of anti-phencyclidine sera, 0.1 mL of serum specimen, an iodinated tracer, and a solid-phase separation. Phencyclidine metabolites do not show significant cross reactivity, but several phencyclidine analogs do cross react. Within-run coefficients of variation for human and dog serum ranged from 2.5 to 13% for concentrations from 2.0 to 500 micrograms/L. Day-to-day coefficients of variation for human and dog serum ranged from 4.3 to 16.7% for concentrations ranging from 2.0 to 90.0 micrograms/L. The sensitivity of the radioimmunoassay is less than 0.5 micrograms/L. Thirty serum specimens from two dogs given 1 mg of phencyclidine per kilogram body weight were analyzed by radioimmunoassay and a gas-chromatographic method. Nonparametric statistical comparison and linear regression showed that results from the two procedures correlate well (r2 = 0.952). Concentration-time data from the two dogs are presented to illustrate the utility of the radioimmunoassay for examining phencyclidine disposition.

The urban epidemic of phencyclidine (PCP) use: clinical and laboratory evidence from a public psychiatric hospital emergency service.

Routine blood samples of 145 consecutive patients seen in the Los Angeles County Psychiatric Hospital Emergency Room during a 48-hour weekday period in June 1979 were examined for phencyclidine (PCP) using a sensitive and specific gas capillary gas chromatographic nitrogen detector (GC2-N) method. Of these 145 samples 63 (43.4%) were positive and PCP levels ranged 0.34 to 142.9 nanograms/ml (mean 14.6 ng/ml +/- 3.4 S.E.M.). An analysis of the records of these 63 patients revealed a wide variety of psychotic clinical pictures resembling mania, depression or schizophrenia with relatively few of the supposedly characteristic manifestations of PCP intoxication. Each of the 63 patients had at least one manifestation of toxic psychosis and/or acute delirium, in addition to the florid symptoms characteristic of functional states. PCP measurement, pharmacokinetics and the possible relationships of this intoxication to the psychiatric manifestations are discussed.