PCP Toxicity Treatment & Management

Updated: Jan 23, 2021
  • Author: Stephan Brenner, MD, MPH; Chief Editor: Stephen L Thornton, MD  more...
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Medical Care

Medical management of intoxication with phenylcyclohexyl piperidine (PCP), also known as phencyclidine, is primarily supportive and encompasses treatment of agitated behavior, seizures, and hyperthermia. Therefore, close monitoring of vital signs including temperature is required. If delirium is severe and compromises patient or staff safety, deep sedation with endotracheal intubation may be necessary.

The American Academy of Child and Adolescent Psychiatry (AACAP) has established a practice parameter guideline for the assessment and treatment of children and adolescents with substance use disorders. [21]

Patients with recent oral use of PCP are candidates for GI decontamination. Activated charcoal (1 g/kg) may be administered and repeated every 4 hours for several doses in most symptomatic patients. Activated charcoal adsorbs PCP and increases its nonrenal clearance. [22] Because mental status can abruptly change, ipecac syrup and GI lavage are not recommended for GI decontamination.

Because PCP is a weak base, treatment in the past included acidification of the patient's urine to increase the drug's urinary excretion. This therapy is no longer recommended because severely intoxicated patients are at risk for acidosis and rhabdomyolysis and because the acidification of urine promotes the precipitation of myoglobin within the renal parenchyma. Furthermore, urinary acidification has never been proven to decrease morbidity or mortality. Because of its large volume of distribution, PCP is not effectively removed with hemodialysis or hemoperfusion.

Patients intoxicated with PCP have been known to demonstrate violent behavior, and they can often present a danger to the clinical staff. The most important approach to management of agitated behavior is the implementation of safe physical restraints and chemical sedation. Benzodiazepines are usually effective in managing aggressive behavior.

Anxiety and agitation can be managed by decreasing external stimuli such as noise, light, and touch. Benzodiazepines are the first means in anxiety treatment, and large doses may be required in severely agitated patients. Benzodiazepines also reduce the occurrence of vivid dreams.

Phenothiazines and butyrophenones should be avoided because they may cause significant hypotension, worsen hyperthermia, exacerbate any anticholinergic effect, may induce dysrhythmias, lower the seizure threshold, and cause dystonic reactions. Acute dystonic reactions can be controlled with diphenhydramine.

Seizure activity is seen in approximately 3% of patients presenting with PCP intoxication. Seizures should be treated with benzodiazepines, followed by barbiturates, propofol, or both.

In some patients severe hypertension with end-organ effects may persist even after the use of benzodiazepines. Phentolamine or nitroprusside are the agents of choice in such cases in order to achieve adequate blood pressure control.

Management of hyperthermia should include aggressive mechanical cooling. In profoundly hyperthermic (> 40.5°C) patients, rapid sequence induction with endotracheal intubation and paralysis should be considered if no response to more conservative measures is noted.

Rhabdomyolysis requires adequate hydration with normal saline in order to maintain a urine output of 2-3 mL/kg/h, as well as close monitoring of creatine phosphokinase (CPK) levels.

Admit the patient who has ingested phenylcyclohexyl piperidine (PCP), also known as phencyclidine, to an ICU if evidence of hyperthermia, seizure activity, or rhabdomyolysis is present.



A medical toxicologist or the staff at a regional poison control center may provide additional information about PCP intoxication and about current patient care recommendations.


Long-Term Monitoring

Refer the patient for drug rehabilitation.

Because of its long-lasting side effect of inducing or unmasking psychopathologic symptoms, continued outpatient therapy including prolonged use of tranquilizers may be necessary for patients after PCP intoxication. [23]