Acute Psychosis In The Emergency Department

by Elizabeth Bassett, Nidal Moukaddam, and Veronica Tucci


Acute psychosis may be encountered on a daily basis in the emergency department (ED). Psychosis is characterized by disorganized thinking, delusions (false, unshakable beliefs), and hallucinations, often auditory, visual. Acute psychosis can also be accompanied by behavioral changes and agitation that are not necessarily commensurate with the severity of psychotic symptoms. The role of the emergency physician, in addition to medically stabilizing and treating acute agitation/psychosis, is to determine whether the patient is experiencing symptoms related to primary psychiatric diagnosis or secondary to a medical illness. This can be challenging given both the limited time and history available to the emergency physician, and the often-noted lack of cooperation of acutely psychotic patients, known to be amongst the hardest amongst patients in the emergency room. The distinction, however, is critical, as incorrectly diagnosing a patient’s behavior as primarily psychiatric in nature, and missing causes of altered mental state (AMS), can lead to dire consequences for the patient. This chapter will cover management aspects of psychosis in the ED.

Case Presentation

A 25-year-old female is brought in by police after being found in a gas station, behaving bizarrely, talking to herself. The patient has no identification, cannot provide her name, and no medical history is available. She is responding to internal stimuli, responds to questions with inappropriate laughter and illogical statements such as “look, a bird, I am queen, meow, what, Jesus, leave me alone,” and not making eye contact with staff. She is noted to be paranoid, repeatedly looking at the air vent above her bed. Initially calm, she became violent after attempts to establish IV access. Verbal de-escalation and redirection were not fruitful. The patient was placed in physical restraints and eventually required emergency pharmacologic intervention. Initial vital signs are Temperature 100.1 Fahrenheit (38.4 degree Celsius), HR 120 bpm, BP 110/75 mmHg, RR 24 per minute, O2 saturation 98%. A liter of IV fluids is given, and an hour later the patient is sleeping, physical restraints are removed, and all vital signs are within normal limits.

The patient wakes up again, slightly calmer, but is perseverating on being pursued by a dark organization which can read her mind, and wants to cast her in a pornographic video. She insists that the technician assigned to the ED is an agent of evil, and refuses further vital signs. She also refuses oral medications, and when asked if pregnant, lowers her voice and says “that’s why they’re after me, help me please.” She refuses to provide further history, and from that point on, becomes mute.

General Approach and Critical Bedside Actions

  1. Ensure the safety of the patient and the medical staff. Have a low threshold to call security personnel early as unsafe behavior can escalate quickly. Physical restraints and medications may be required early on.
  2. Recognize abnormal vital signs.
  3. Have the patient put on a telemetry monitor and establish IV access.
  4. Assess for immediately life-threatening and reversible causes of psychosis. Check a point of care glucose for hypoglycemia, check oxygen saturation for hypoxemia, and expose the patient to look for evidence of trauma.
  5. Perform a head to toe complete physical exam with attention to neurologic exam.

Differential Diagnosis

  1. Primary psychiatric etiology: schizophrenia versus schizoaffective disorder, depression with psychotic features, bipolar disorder with psychotic features
  2. Hypoglycemia
  3. Drug or alcohol intoxication or withdrawal
  4. Substance-induced psychosis (think stimulants, e.g., amphetamines, synthetic cannabinoids)
  5. Infection – either systemic or central nervous system (think sepsis or encephalitis)
  6. Central nervous system lesion (particularly in patients with a history of cancer of AIDS)
  7. Intracranial bleed (especially if evidence of trauma or anticoagulated patient)
  8. Hyperthermia/heat stroke (unlikely with a temperature of 100.1, however, checking a rectal temperature may reveal significantly higher core body temperature)
  9. Hypoxia/hypercarbia (unlikely given this patient’s pulse oximetry reading)
  10. Vitamin deficiencies (Wernicke’s)
  11. Hypotension/hypoperfusion (unlikely with systolic of 110 unless the patient routinely has markedly elevated blood pressure values)
  12. Thyrotoxicosis

History Taking and Physical Examination Hints

History Taking Hints

A patient with acute psychosis may be a poor historian and collateral information (from police, Emergency Medical Services, or patient’s family) is often helpful. Make every effort to meet with them at the time of arrival, as such information may not be available later on. For our patient, no history is available; however, in general, the key information sought includes:

  1. Pick up location: Street, home, nursing home? Get contact information of the family or nursing home if available, including prescribed medications. If the patient was from home or nursing home, was any medical history provided such as a history of mental illness or past similar episodes. The absence of previous psychiatric history strongly suggests a medical cause of the behavior.
  2. Timing: When was the patient last seen at baseline? Has the onset of abnormal behavior been gradual or rapid? Rapid onset suggests underlying medical condition or drug use.
  3. What did the scene look like: Empty pill bottles, alcohol, illicit drugs, a potential for other toxic exposures? Were there any prescription medications at the scene? Obviously, the presence of prescription anti-psychotics can help with the diagnosis but the entire medication list can help with determining the patient’s past medical history and may be the key in diagnosis if the etiology is medical in nature.
  4. Vitals and blood sugar of the patient en route to the hospital if available.
  5. The mental status of the patient at the scene vs. on arrival. Is there a waxing and waning course? Is the patient’s mental status improving or declining?
  6. Has the patient been starving themselves because of psychotic beliefs?
  7. How paranoid is the story the patient is telling you? While individuals may indeed be the target of mysterious organizations, most paranoid, persecutory delusions are extremely unlikely.
  8. Do they have pre-existing medical conditions they have been neglecting because of their psychosis? Many patients with mental illness have medical comorbidities, often poorly treated.

Physical Examination Hints

It is imperative that a head to toe exam be performed. This may be the only full physical exam that the patient receives while in the hospital and therefore the only opportunity to assess for traumatic or medical reasons for the symptoms at hand.

  1. HEENT: Look for evidence or recent trauma – lacerations, abrasions, hematoma, basilar skull fracture (raccoon eyes, battles sign, CSF or blood in the ears). Look for evidence of past traumatic brain injury as evidenced by old neurosurgical scars.
  2. Eyes: Pay special attention to the ocular exam. Assess for pupil size and responsiveness to light, presence or absence of extra-ocular eye movements, and presence of nystagmus. Ocular findings can be a clue towards various toxidromes or space-occupying lesions.
  3. Neck: Assess for meningismus and thyromegaly
  4. Pulmonary: The presence of rales, wheezing can be a clue that the patient is experiencing hypoxia secondary to CHF, COPD, or asthma. Hypoxia can be a cause of the patient’s altered mental status although unlikely if the patient’s oxygen saturation is high. Rales or diminished breath sounds may be a clue, especially in elderly patients, that the AMS is secondary to a pulmonary infection.
  5. Cardiac: This exam is unlikely to aid in the diagnosis; however the presence of an irregularly irregular heartbeat may indicate that the patient is anticoagulated and therefore at increased risk of spontaneous or traumatic intracranial bleed. Tachycardia or bradycardia may also indicate various toxidromes.
  6. Abdomen: Assess for rigidity suggesting trauma or infection. Look for evidence of encephalopathy: hepatomegaly, ascites, caput medusae
  7. Skin: Assess for rashes, petechiae, track marks. This can be a clue to infection, trauma, intoxication, or withdrawal.
  8. Neurologic: A complete neurologic exam is often difficult to perform as it requires cooperation on the part of the patient. Assess for cranial nerves, strength, sensation, coordination, reflexes, and gait; focal deficits suggest a medical cause of psychosis.

Emergency Diagnostic Tests and Interpretation

The lab and radiologic studies are dependent on the clinical presentation. Indicated studies may include electrolytes, acetaminophen levels, salicylate levels, LFTs, ammonia, PT/INR, thyroid studies, HIV, pregnancy test, ECG, CXR, UA, urine culture, blood culture, CT head, LP. Increasing age, preexisting medical comorbidities, the absence of past psychiatric history warrant, whereas young patients with a known psychiatric history, normal vitals/physical exam, a classic toxidrome or admitted drug use may not require lab or imaging studies unless the patient’s mental status fails to improve on serial assessments. Evidence or trauma, the use of anticoagulants, or an abnormal neurologic exam should prompt a CT head to assess for a bleed or lesion. However, note that inpatient psychiatric facilities may require testing independent of clinical status.

Emergency Treatment Options

These are divided into medical and psychiatric.

Initial Stabilization

As always, ensure airway, breathing, and circulation. Ensure a safe and if possible, a low-stimulus environment to minimize agitation. This may be done by attempting to redirect the patient verbally and turning down the lights and decreasing the number of people in the room. Temporary physical restraints and emergency pharmacologic intervention may be needed if the patient escalates. Psychotic patients will benefit from an antipsychotic agent.


Antipsychotics and benzodiazepines are the mainstays of treatment for acutely psychotic patients who are agitated or violent. These may be given alone but are often given in conjunction and will be beneficial not only to the patient with psychosis secondary to primary psychiatric condition but also in various sympathomimetic toxidromes as well.

  1. Benzodiazepines: For the acutely agitated patient, the benzodiazepines of choice are typically midazolam and lorazepam, given intravenously or intramuscularly. Midazolam may be preferred as it has a shorter time of onset as well as a shorter duration of action compared to lorazepam. Generally, diazepam is avoided due to its long half-life. In the elderly or pediatric patients, use lower doses. Watch for paradoxical disinhibition.
  2. First-generation antipsychotics: haloperidol and Droperidol. Potential side effects include extrapyramidal side effects, e.g., dystonic reaction, as well as potential arrhythmias, especially long QT leading to torsades. When possible, get a baseline ECG prior to administration.
  3. Atypical Antipsychotics: Olanzapine, Ziprasidone, Quetiapine, Risperidone. These drugs also cause QT prolongation but generally have fewer extrapyramidal side effects.

Disposition Decisions

  1. Admission to the hospital: This is appropriate in patients with an identified underlying medical cause of psychosis or patient’s in whom no underlying medical cause has been found, but a medical condition is suspected, for example, patients with no prior psychiatric history or patients with abnormal vitals. Inpatient admission may be necessary to follow up on studies, particularly cultures.
  2. Discharge to home: This may be appropriate for patients with substance-induced psychosis who, either with the help of medications or simply the tincture of time, have returned to their baseline mental status.
  3. Admit to the psychiatric facility: This is appropriate for patients with higher symptom burden who have been medically cleared; dangerousness to self or others, or inability are unable to care for themselves due to psychosis warrant admission.

References and Further Reading

  • American College of Emergency Physicians. Critical issues in the diagnosis and management of the psychiatric patient in the emergency department. Ann Emerg Med 2006; 47: 79-99
  • American College of Emergency Physicians. Clinical policy for the initial approach to patients presenting with altered mental status. Ann Emerg Med 1999; 33:251-281
  • Nassasi, D. ED Management of Delirium and Agitation. Emergency Medicine Practice 2007; 9 (1). Retrieved from – link