Cases that Test Your Skills
The psychotic pot smoker
When police bring Mr. C to the emergency department, he’s agitated, confused, and hallucinating. He claims someone tampered with his marijuana. What’s causing his psychosis?
CASE: Scared and confused
Mr. C, age 28, presents to the emergency department (ED) in police custody with agitation and altered mental status. Earlier that evening, Mr. C’s girlfriend noticed he was talking to himself while watching television. A few hours later, Mr. C thought someone was breaking into his house. Mr. C ran out of the house screaming for help, broke his neighbor’s window, and eventually called the police. When the police arrived Mr. C was wearing only his underwear, shaking, and bleeding from his hands. He said he was afraid and refused to respond to police instructions. Police officers used an electronic stun gun to facilitate transport to the hospital.
Mr. C admits to smoking 3 to 4 marijuana joints daily for the past 16 years. His last drug use was 2 hours before his symptoms began. Mr. C suggests that someone may have adulterated his marijuana joint but he has no factual basis for this accusation. He denies using alcohol and other illicit drugs and has no personal or family psychiatric history. He denies recent fever, loss of consciousness, chest pain, weakness, myalgia, or headache. Medically stable, his only complaint is mild hand pain.
Mr. C is alert, awake, and oriented to his name, and he responds properly to questions. He is tachycardic (101 bpm), his blood pressure is 149/57 mm Hg with normal S1 and S2 sounds, and he has no meningismus or nystagmus. Glasgow Coma Scale score is 15. He has increased deep tendon reflexes on the right upper and lower limb with good hand-grip and multiple abrasions and lacerations on his hands.
The authors’ observations
New-onset psychosis can have a wide differential diagnosis, particularly when reliable history is not available. Mr. C’s allegation that someone tampered with his marijuana raises 2 possibilities: embalming fluid (form-aldehyde) toxicity or PCP intoxication.
Embalming fluid toxicity can cause:
- agitation and sudden unpredictable behavior
- confusion or toxic delirium
- coma or seizure
- cerebral and pulmonary edema or death in severe cases.
The terms “wet,” “sherm,” “fly,” “amp,” or “illy” are used to describe a marijuana cigarette that has been dipped into embalming fluid, dried, and then smoked.1 The effect is similar to that of PCP and causes extreme hallucinations. Reported highs last 30 minutes to 1 hour.2
Symptomatology of PCP intoxication may be indistinguishable from functional psychosis (Table 1).3 Visual, auditory, and tactile misperceptions are common and highly changeable disorientation often is accompanied by alternating periods of lethargy and fearful agitation. These patients typically show catatonic posturing and/or stereotyped movement. Somatic sensations appear to be disassociated; patients may misperceive pain, distance, and time. Patients taking PCP rarely admit to true hallucinations; however their thinking usually is grossly disoriented.4 Symptoms of delirium may last from 30 minutes to 6 hours in 80% of cases; 12% of patients may remain symptomatic for 12 hours. Violent behavior and agitation usually lasts only a few hours.5
Long-term marijuana abuse can lead to psychosis6 but acute onset is not typical, and recent prospective trials raised doubts that cannabis would be a sole factor.7 Instead, cannabis may be 1 of several factors that contribute to psychosis, particularly in patients who are predisposed.
Phencyclidine (PCP) intoxication: What to look for
Percentage of cases
No behavior effect
Grand mal seizure
Source: Reference 3
Possible neurologic causes
Complex partial seizures—also known as psychomotor epilepsy—are caused by a surge of electrical activity in the brain. Seizures often involve 1 of the brain’s temporal lobes but can affect any brain region. Symptoms include:
- impaired social interaction
- inability to control one’s movements
Episodes typically start with a blank stare followed by automatisms. The actions and movements often are unorganized or confused. Motor symptoms typically last for 1 to 2 minutes and confusion persists for another 1 to 2 minutes.8 In rare cases, a patient may become agitated or engage in behaviors such as undressing. Complex partial seizures may cause a person to run in apparent fear, cry out, or repeat a phrase.9 Electroencephalogram, CT, MRI, or positron-emission tomography scan could reveal any intracranial focus of complex partial seizures.
We suspect PCP or embalming fluid intoxication and initiate supportive therapy.
EVALUATION: Still confused
Initial baseline labs include a urine drug screen (UDS), chest radiography, ECG, and head CT. Mr. C’s UDS is positive for cannabis. A specific PCP assay is negative. White blood cell count (WBC) is 22,000/μL with high neutrophil count (88%), creatine kinase (CK) is 458 U/L, and urinalyis reveals protein 75 mg/dL and ketone 50 mg/dL. Head CT is negative for any acute process (click here for detailed description of Mr. Cï¿½s hospital course while in the ED).
During psychiatric evaluation 7 hours after presentation, Mr. C’s speech is loose and somewhat pressured, but intelligible. He cannot follow commands. Mr. C is delusional and appears to be hallucinating. He can repeat 3 words immediately but not after 3 minutes. We start Mr. C on divalproex, 1,500 mg/d, haloperidol, 6 mg/d, and IV lorazepam, 2 mg as needed for agitation. Although mildly disoriented, he gradually becomes less agitated.
The authors’ observations
At this point further evaluation is needed. Mr. C’s elevated WBC count could explain his fluctuating symptoms. He cannot provide further history and his family denies any past psychiatric episodes. Thyroid-stimulating hormone, B12, and folate levels are within normal limits. A negative LP rules out meningitic infection. We give Mr. C a diagnosis of psychosis NOS (Table 2).10
DSM-IV-TR criteria for psychotic disorder, not otherwise specified
This category includes psychotic symptomatology (ie, delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior) about which there is inadequate information to make a specific diagnosis or about which there is contradictory information, or disorders with psychotic symptoms that do not meet the criteria for any specific psychotic disorder. Examples include:
Source: Reference 10
TREATMENT: Medication choices
After 8 hours in the ED, Mr. C is transferred to the medical unit, where he becomes agitated and complains of auditory and visual hallucinations. He receives divalproex, 750 mg, haloperidol, 3 mg, and IM diphenhydramine, 50 mg, to calm him. He remains agitated but not violent until bedtime. At midnight he is agitated and violent and receives another dose of haloperidol and IM diphenhydramine with IV lorazepam, 2 mg. These medications calm him and he is able to sleep until morning.
Morning labs reveal CK is 674 U/L and WBC decreased to 13,200/μL. Mr. C denies any distress but after the fourth dose of haloperidol, he develops dystonia of his arms so we discontinue this medication. We start aripiprazole, 10 mg/d gradually increased to 30 mg/d, and Mr. C receives 1 injection of diphenhydramine. He responds well to the treatment.
The next few hours are uneventful but then Mr. C becomes verbally abusive to his relatives and sitter; physical restraints are ordered and he receives IM ziprasidone, 20 mg, and IV lorazepam, 2 mg. He remains awake and babbling. His perception continues to wax and wane and his words are jumbled. He remains calm until the next morning (click here for detailed description of Mr. Cï¿½s hospital course while on the medical unit).
After 4 days on the medical unit Mr. C is transferred to the psychiatry unit, where he is angry, belligerent, and hostile, but not placed in restraints. His symptoms resolve in 2 days without any further episodes of violent behavior.
OUTCOME: Solving the puzzle
When Mr. C becomes cooperative, he gives a detailed history. He repeats his suspicion of smoking adulterated marijuana, but during detailed questioning, he admits to using alprazolam, which he purchased illegally, to sleep for the past 6 to 7 months. He started with 1 or 2 “footballs” (1 to 2 mg) and gradually increased to 3 or 4 “bars” (6 to 8 mg) each day. Mr. C could no longer afford the drug and last took alprazolam 6 days before his symptoms began. He says that after stopping alprazolam he felt anxious and could not sleep. His girlfriend adds that he was irritable and “he had not been acting himself” several days before admission. She says he complained of hearing the voice of God, particularly when he was not taking alprazolam.
Mr. C’s hand wounds heal and his vitals are normal during his 1-week stay on the psychiatric unit. His interactions with staff and peers improve. Aripiprazole is tapered and discontinued; divalproex is reduced to 1,000 mg/d. Mr. C is discharged 11 days after presentation and prescribed divalproex, 1,000 mg/d, with instructions to taper the drug over several days to prevent withdrawal seizures before stopping it in 1 week.
Mr. C does not return for his follow-up appointment; however, in a telephone follow-up 6 months later, he denies experiencing withdrawal symptoms after discharge. Mr. C is now undergoing drug rehabilitation.
The authors’ observations
Benzodiazepine withdrawal symptoms occur 7 to 10 days after abrupt cessation (Table 3).10 Symptoms are similar to those of alcohol withdrawal and include tachycardia, hypertension, clouding of consciousness, and auditory and visual hallucinations.11 Serious reactions to benzodiazepine withdrawal include seizures and death.12
Because of the high prevalence of poly-substance misuse, obtain a detailed substance use history in patients undergoing benzodiazepine withdrawal to determine the likelihood of polysubstance withdrawal.13 A cross-tolerant sedative such as clonazepam could prevent withdrawal symptoms as the dose is gradually decreased. Long-acting benzodiazepines such as clonazepam or diazepam are recommended.14
In Mr. C’s case, minor withdrawal symptoms, such as disturbed sleep and irritability, began 3 to 4 days after discontinuing benzodiazepines15 and preceded development of psychosis. Withdrawal symptoms usually resolve after 2 weeks.16 Mr. C responded only partially to IV lorazepam because he did not receive the total replacement dose. Had we known he was experiencing benzodiazepine withdrawal, Mr. C could have been managed with detoxi"cation of the primary drug, alprazolam, with diazepam substitution and tapering over 3 weeks.17
Criteria for sedative, hypnotic, or anxiolytic withdrawal
A. Cessation of (or reduction in) sedative, hypnotic, or anxiolytic use that has been heavy and prolonged
B. Two (or more) of the following, developing within several hours to a few days after Criterion A:
C. The symptoms in Criterion B cause clinically significant distress or impairment in social, occupational, or other important areas of functioning
D. The symptoms are not due to a general medical condition and are not better accounted for by another mental disorder
Source: Reference 10
- Vikander B, Koechling UM, Borg S, et al. Benzodiazepine tapering: a prospective study. Nord J Psychiatry. 2010; 64(4):273-282.