Phencyclidine Toxicity Treatment & Management

Updated: Mar 28, 2022
  • Author: Patrick L West, MD; Chief Editor: Michael A Miller, MD  more...
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Prehospital Care

Evaluate and stabilize the patient's airway, breathing, and circulation (ABCs) and provide cervical spine immobilization if traumatic injury is suspected.

Physical restraints may be required to prevent self-injury and to protect the medical staff. These patients should be monitored closely due to several reports of death in PCP-intoxicated patients who were being physically restrained.

Chemical restraints may also be used. Establish intravenous access and administer benzodiazepines for patients with severe agitation. Intramuscular benzodiazepines are an alternative if intravenous access is unobtainable.


Emergency Department Care

After addressing and stabilizing the ABCs, treatment of PCP intoxication starts with initial supportive measures (intravenous fluid, supplemental oxygen, cardiac monitoring). An electrocardiogram may be indicated to assess for dysrhythmias. Obtain a fingerstick to rule out hypoglycemia. Place patients in a dark, quiet room under continuous observation to minimize environmental stimuli.

Consider activated charcoal for oral ingestions and co-ingestions. Multiple doses of charcoal may be beneficial in the case of large overdose. Only one dose of sorbitol should be given, usually with the initial dose. Clinicians should be aware that administration of activated charcoal to a patient with an unprotected airway can convert relatively benign exposure (eg, mild PCP intoxication) into a very serious condition (eg, aspiration pneumonia).

Patients exhibiting extremely violent psychotic behavior require sedation with parenteral benzodiazepines. Seizures should be treated with benzodiazepines. Haloperidol should be reserved for patients with mild, predominantly psychotic, symptoms and normal vital signs. Butyrophenones (haloperidol, droperidol) and phenothiazines (eg, chlorpromazine) should be avoided in moderate and severe intoxications because they can lower seizure threshold, cause dystonic reactions, induce hypotension, and worsen anticholinergic smanifestations, including hyperthermia.

Hyperthermia may be treated by conventional cooling methods.

Rhabdomyolysis is treated with intravenous hydration, urine alkalinization, and osmotic/diuretic agents. A possible caveat is the theoretical, but clinically unproven, concept of increased PCP reabsorption secondary to the urine alkalinization.

For hypertensive emergencies, try to control agitation first with parenteral benzodiazepines. For persistent hypertension, intravenous nitroprusside is the agent of choice. Because of the theoretical concept of unopposed alpha effect (worsening of hypertension) and the availability of other antihypertensive agents (eg, calcium-channel blockers, intravenous nitroglycerin), pure beta-blockade should be avoided. Even labetalol, which has both alpha- (weak) and beta-blocking abilities, can be given only after alpha-blockade with phentolamine is achieved.

Acute PCP toxicity can usually be managed conservatively with an observation period of a few hours. More serious ingestions may require admission to an intensive care unit for days to weeks.

Any patient with evidence of unrelenting agitation, hypertensive crisis, hyperthermia, seizures, respiratory depression, rhabdomyolysis, or severe traumatic injuries should be admitted to the hospital, and possibly to an intensive care setting if indicated.

Consider a psychiatric evaluation for substance abuse counseling and/or suicidal ideations. Consider referral to a drug rehabilitation program. Repeated use of PCP can result in addiction, and abrupt discontinuation of the drug can produce withdrawal symptoms, including craving, confusion, and depression.



Consult with a board-certified medical toxicologist or a local poison control center for further recommendations.