Hallucinogen Toxicity Treatment & Management

• Focus prehospital care on preventing patients from harming themselves or others and transporting them to an appropriate facility for further evaluation. Calm, reassuring, and nonthreatening behavior can be useful in "talking down" patients to allow care and interventions to proceed.
• Appropriate use of physical and chemical restraints may be required. Benzodiazepines are probably the safest sedatives and can be effective for calming and restraining most patients. However, these agents are best administered intravenously, necessitating intravenous access before administration.
• Avoid use of antipsychotics, particularly haloperidol or droperidol, in patients who may have ingested PCP or other agents with significant adrenergic stimulant effects. Cardiac dysrhythmias and seizures could result from the combination of these agents.
• If use of physical restraint is necessary, the team approach, using at least 5 persons, should be effective in quickly subduing and restraining the patient and minimizing risks of additional injury to patient or rescuers.

Lysergic acid diethylamide

Once patients have been evaluated for significant trauma and other potential etiologies, place them in quiet rooms with diminished lighting and other stimuli. Patients may require sedation with benzodiazepines, but, generally, supportive reassurance that the hallucinations are not real or dangerous is adequate care. The toxic psychosis generally resolves in 2-4 hours.

If patients do not respond to supportive care and benzodiazepines, or they demonstrate a frank psychotic break, haloperidol (2-5 mg IM q1-2h) may be necessary to control the toxic psychosis.

Chronic and intermittent psychotic states resulting from LSD use are well described. Patients may unmask underlying psychotic behavior or develop new psychoses or personality disorders. Posthallucinogen perceptual disorder (ie, flashbacks) occurs in most patients who have taken LSD more than 10 times. These episodes are generally perceptual alterations or pseudohallucinations produced by sudden changes of lighting. Occasionally, more bizarre and frightening images reoccur. Treatment of these episodes is supportive; they may be managed as panic attacks with benzodiazepines.

Intoxication usually lasts 8-12 hours, but psychotic behavior may be present for days. Patients generally can be observed until the acute intoxication has cleared and mental status has returned to normal. Patients without residual effects or psychosis can be discharged safely with suggested follow-up in a few days. Admit any patient with prolonged toxic effects for observation until the toxic symptoms resolve or the patient has had psychiatric evaluation for persistent psychotic behavior.

Phencyclidine and ketamine

General supportive management is important, as is adjusting the environment to decrease stimulation and agitation. After screening patients for potential injury or other causes of behavior, they should be secluded, if possible. Use physical restraints for extremely combative patients and sedate them with benzodiazepines. Large amounts of benzodiazepines may be needed to sedate the patient, and supportive airway management may be indicated.

Manage frankly psychotic behavior with combinations of benzodiazepines and haloperidol. Use phenothiazines with caution because the potential for seizures and cardiovascular compromise exists in patients experiencing significant sympathomimetic effects. Be aware that the dissociative anesthetic properties of phencyclidine and ketamine may allow patients to appear far stronger than they are and to be insensitive to painful feedback.

Psilocin and psilocybin

For most patients, care consists of placement in a subdued and supportive environment. Frank psychoses rarely occur. Aggressive and destructive behaviors are also uncommon.

Anxiety and agitation can be managed with benzodiazepines, and antiemetics may help GI complaints. Intoxication can last several hours and may wax and wane with a larger ingestion.

Mescaline

Anxiety and intense agitation may occur carefully monitor the patient for potential hemodynamic compromise and respiratory depression.

As with the other hallucinogens, a subdued and supportive environment is important. Patients with respiratory depression may require ventilatory assistance; intubation is indicated in cases of significant intoxication because of the potential for aspiration secondary to CNS depression. Initiate intravenous crystalloid fluid boluses to treat hypotension. Benzodiazepines are indicated for the agitated patient.

Designer drugs

Care of patients who have ingested any of these substances is primarily supportive and focused on decreasing adverse stimuli. Benzodiazepines are used to reduce agitation and induce sedation. Intravenous sodium nitroprusside may be required to manage hypertensive emergencies. Avoid beta-blockers because unopposed alpha-adrenergic properties may lead to hypertensive crises. Management of seizures includes administration of benzodiazepines and phenytoin (Dilantin).

If significant hyperthermia is present, initiate cooling measures and evaluate the patient for rhabdomyolysis. Some evidence suggests that the combination of marijuana and MDMA delays the onset but prolongs the duration of temperature elevation. Observation for a longer period of time, as well as aggressive cooling measures, may be indicated with this drug combination.^[10] This combination may also lead to significantly higher heart rates. Perform early aggressive hydration if evidence of rhabdomyolysis is present.

Management of hypertensive crisis may require the use of sodium nitroprusside or nitroglycerin infusions to rapidly control blood pressure.

• Management of simple hallucinogen intoxications does not require routine consultation with behavioral health specialists. However, consultation with behavioral health specialists and possible inpatient care is indicated for patients who have complicated ingestion responses with acute psychosis or destructive behaviors. Refer patients with a history of substance abuse for behavioral health evaluation.
• Consult with a toxicologist or regional poison control center for patients requiring admission for management of severe intoxications.