Psychiatry · Year 3 · from Psychiatry

Case 2: Acute Agitation with Unknown Etiology

Patient Demographics

  • Age: 35 years old
  • Sex: Male
  • Occupation: Unknown

Chief Complaint

Per EMS: "Found in the street yelling at cars. Very agitated, combative."

History of Present Illness

The patient is a 35-year-old man brought by EMS after being found in the middle of a busy street at 2 AM, yelling incoherently at passing cars. Bystanders called 911 when he began throwing objects at vehicles. EMS reports he was combative and required restraint for transport. He is unable to provide coherent history.

Witnesses report he appeared to be talking to someone who wasn't there. No identification on his person. No collateral available. No known medical or psychiatric history.

Initial Presentation

Vital Signs:

  • Temperature: 101.4°F (38.6°C)
  • Heart rate: 128 bpm
  • Blood pressure: 168/102 mmHg
  • Respiratory rate: 22
  • O2 saturation: 96% on room air
  • Pupils: 6 mm bilaterally, reactive

Physical Examination:

  • General: Agitated, diaphoretic, combative
  • Skin: Flushed, diaphoretic, no track marks visible
  • Neuro: Moving all extremities, grossly non-focal (limited exam)
  • Unable to complete detailed exam due to agitation

Mental Status Examination (Limited)

Appearance: Disheveled, flushed, diaphoretic

Behavior: Severely agitated, yelling, striking at staff, requires multiple security officers

Speech: Loud, pressured, incoherent

Mood: Unable to assess

Affect: Agitated, labile, fearful

Thought Process: Disorganized, incoherent

Thought Content: Appears paranoid (yelling "get away from me"), unable to assess formally

Perceptions: Appears to respond to internal stimuli (talking to someone not present, looking at empty space)

Cognition: Unable to assess - not cooperative; appears disoriented

Differential Diagnosis

Medical Causes (Must Rule Out First):

  • Substance intoxication (stimulants, PCP, synthetic cannabinoids, anticholinergics)
  • Substance withdrawal (alcohol, benzodiazepines)
  • Delirium (infection, metabolic, CNS pathology)
  • Hypoglycemia
  • Hyperthyroidism/thyroid storm
  • Seizure/postictal state
  • Meningitis/encephalitis
  • Intracranial pathology (hemorrhage, mass, trauma)

Psychiatric Causes:

  • Acute psychotic episode (schizophrenia, brief psychotic disorder)
  • Manic episode with psychosis
  • Severe anxiety/panic

Immediate Management

1. Safety and De-escalation Attempt:

  • Multiple staff present (show of force)
  • Attempt verbal de-escalation: "We're here to help you. You're safe. Can you tell us what's going on?"
  • Patient remains combative, non-redirectable

2. Pharmacological Management (verbal de-escalation failed):

  • Given agitation with unknown etiology, avoid antipsychotics initially (could worsen underlying condition)
  • Lorazepam 2 mg IM given for sedation
  • Patient somewhat calmer after 20 minutes, still agitated

3. Diagnostic Workup:

  • Labs ordered STAT:
  • Glucose: 94 mg/dL (normal - rules out hypoglycemia)
  • CBC: WBC 14.2 (elevated)
  • CMP: Normal
  • Urine drug screen: Positive for amphetamines
  • Blood alcohol: Negative
  • TSH: Normal
  • Ammonia: Normal
  • CT Head without contrast: No acute intracranial abnormality
  • Urinalysis: Normal
  • Chest X-ray: Normal

4. After Results - Updated Assessment:

Positive amphetamines on UDS suggests:

  • Methamphetamine intoxication
  • Prescription amphetamine (Adderall) intoxication
  • Synthetic cathinones ("bath salts") - may not show on standard screen

Clinical Picture Consistent with Stimulant Intoxication:

  • Agitation
  • Tachycardia
  • Hypertension
  • Hyperthermia
  • Mydriasis
  • Paranoia
  • Possible tactile hallucinations
  • Diaphoresis

Revised Treatment Plan

Stimulant Intoxication Management:

1. Supportive Care:

  • Quiet, low-stimulation environment
  • IV access, fluids for dehydration
  • Cooling measures for hyperthermia

2. Benzodiazepines (first-line for stimulant-induced agitation):

  • Lorazepam 2 mg IM/IV every 30-60 minutes PRN
  • Addresses agitation, reduces cardiovascular strain, lowers seizure risk
  • More effective than antipsychotics for stimulant agitation

3. Avoid:

  • Antipsychotics as first-line (can worsen hyperthermia, lower seizure threshold)
  • Physical restraints if possible (increase hyperthermia, rhabdomyolysis risk)
  • Beta-blockers (risk of unopposed alpha-agonism)

4. Monitoring:

  • Continuous cardiac monitoring
  • Temperature every 30 minutes
  • Watch for:
  • Seizures
  • Rhabdomyolysis (check CK if persistent hyperthermia)
  • Cardiac arrhythmias

Hospital Course

2 hours post-presentation:

  • Total lorazepam 6 mg IM
  • Temperature 99.8°F (improving)
  • HR 98, BP 148/88
  • Calmer, able to answer questions

Updated History (when able to communicate):

  • States he used "crystal" (methamphetamine) approximately 12 hours ago
  • Has been bingeing for 3 days with minimal sleep
  • Chronic methamphetamine use disorder
  • No psychiatric history when not using
  • Experienced "shadow people" (meth-induced hallucinations)

Diagnosis:

  • Amphetamine-type Substance Intoxication, Severe (F15.129)
  • Amphetamine-type Stimulant Use Disorder, Severe (F15.20)

Disposition:

  • Psychiatry observation overnight for resolution of intoxication
  • Repeat mental status exam when sober
  • Substance use treatment referral
  • If psychosis resolves completely with sobriety, likely substance-induced rather than primary psychotic disorder

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