Psychiatric & Behavioral Health

What is Generalized Anxiety Disorder (GAD)?

A chronic disorder of excessive, difficult-to-control worry about multiple life domains occurring more days than not for at least 6 months, accompanied by somatic symptoms such as restlessness, fatigue, irritability, muscle tension, or sleep disturbance.

Why can GAD never be a first-visit ED diagnosis in a patient with chest pain or dyspnea?

Anxiety is a diagnosis of exclusion in the ED; ACS, PE, arrhythmia, hyperthyroidism, and hypoglycemia present identically and must be excluded before attributing symptoms to anxiety.

What organic conditions mimic GAD in the ED?

Hyperthyroidism, hypoglycemia, pheochromocytoma, arrhythmia (especially SVT), PE, carcinoid, stimulant or caffeine intoxication, and alcohol or benzodiazepine withdrawal.

What is the standard ED screening and workup for suspected anxiety disorder?

GAD-7 for screening plus ECG, glucose, TSH, CBC, BMP, urine drug screen, and pregnancy test as indicated; broaden the workup if vitals are abnormal or onset is new after age 45.

What is the appropriate ED pharmacologic management of acute severe anxiety?

Verbal reassurance and a quiet environment first; a single low-dose benzodiazepine (lorazepam 0.5 to 1 mg) only for severe distress, since SSRIs and SNRIs are definitive therapy but require weeks and should be started in the outpatient setting.

Which patients should not receive a benzodiazepine prescription at ED discharge for anxiety?

Elderly patients (fall and delirium risk), patients with substance use disorder, and patients on opioids, given the risk of dependence and respiratory depression.

What is the ED disposition plan for uncomplicated GAD?

Discharge with primary care or psychiatry follow-up for SSRI or SNRI initiation and cognitive behavioral therapy, with return precautions for suicidal ideation or new physical symptoms.

What is Panic Disorder?

Recurrent unexpected panic attacks followed by at least 1 month of persistent worry about additional attacks or maladaptive behavioral change to avoid them.

What defines a panic attack?

An abrupt surge of intense fear or discomfort peaking within 10 minutes with at least 4 symptoms such as palpitations, diaphoresis, tremor, dyspnea, choking, chest pain, nausea, dizziness, chills or heat, paresthesias, derealization, fear of losing control, or fear of dying, typically resolving within 20 to 60 minutes.

What must be excluded before diagnosing panic attack in the ED?

ACS, PE, arrhythmia, pneumothorax, hyperthyroidism, hypoglycemia, pheochromocytoma, cocaine or amphetamine intoxication, and alcohol or sedative withdrawal.

What features of a first panic attack should prompt an aggressive search for organic disease?

First episode after age 45, atypical symptoms, abnormal vital signs, syncope, focal neurologic findings, or onset during exertion.

What is the acute ED treatment of a panic attack?

Calm reassurance and coached slow breathing in a low-stimulus room, with a short-acting benzodiazepine such as lorazepam 0.5 to 1 mg reserved for severe or refractory distress.

Why is paper bag rebreathing no longer recommended for hyperventilation?

It risks significant hypoxia and may delay recognition of true hypoxemic causes such as PE, ACS, or pneumothorax.

What is definitive outpatient therapy for panic disorder?

SSRI or SNRI as first-line pharmacotherapy combined with cognitive behavioral therapy, with benzodiazepines avoided for maintenance because of tolerance and dependence.

What condition frequently coexists with panic disorder and affects ED presentation?

Agoraphobia, which drives avoidance behavior and can cause patients to delay seeking care for genuine medical emergencies.

What are Depressive Disorders?

A group of disorders characterized by persistent depressed mood or anhedonia with associated neurovegetative, cognitive, and somatic symptoms causing functional impairment, of which major depressive disorder is the prototype.

What are the DSM-5 criteria for major depressive disorder?

At least 5 of 9 symptoms for a minimum of 2 weeks, and at least one must be depressed mood or anhedonia; recall with SIGECAPS (Sleep, Interest, Guilt, Energy, Concentration, Appetite, Psychomotor, Suicidality).

What is the single most important task when a depressed patient presents to the ED?

Direct assessment of suicidal ideation, plan, intent, and access to lethal means, since asking about suicide does not increase risk and screening drives disposition.

What medical conditions mimic depression and should be considered in the ED?

Hypothyroidism, anemia, vitamin B12 deficiency, occult malignancy, Parkinson disease, dementia, obstructive sleep apnea, and medication effects from beta-blockers, corticosteroids, interferon, or isotretinoin.

What screening tools are used for depression in the ED?

PHQ-2 as a rapid two-question screen, escalating to PHQ-9 for severity grading if positive.

What is postpartum psychosis and why is it an emergency?

An abrupt psychotic presentation within days to weeks postpartum with delusions, hallucinations, and disorganization that carries high risk of infanticide and suicide, requiring immediate psychiatric hospitalization rather than outpatient management.

What warning applies when starting an SSRI in a patient under 25?

FDA black box warning for increased suicidal ideation and behavior in children, adolescents, and young adults, requiring close follow-up in the first weeks of therapy.

What ED findings favor admission over discharge for a depressed patient?

Active suicidal ideation with plan or intent, psychotic features, inability to care for self, lack of social support, recent attempt, or acute intoxication clouding assessment.

What are Bipolar and Related Disorders?

Mood disorders defined by episodes of mania or hypomania, usually alternating with depressive episodes, with bipolar I requiring at least one manic episode and bipolar II requiring hypomania plus a major depressive episode.

What are the criteria for a manic episode?

At least 1 week of elevated, expansive, or irritable mood with increased energy plus 3 or more DIGFAST features (Distractibility, Impulsivity, Grandiosity, Flight of ideas, Activity increase, Sleep decreased, Talkativeness), or any duration if hospitalization is required.

How does hypomania differ from mania?

Hypomania lasts at least 4 days, causes no marked functional impairment, requires no hospitalization, and by definition includes no psychotic features.

What is the ED management of an acutely agitated manic patient?

Verbal de-escalation and environmental control first, then a second-generation antipsychotic such as olanzapine or ziprasidone, or haloperidol plus lorazepam, with physical restraints only as a last resort and with continuous monitoring.

Why should antidepressant monotherapy be avoided in bipolar disorder?

It can precipitate a manic switch or rapid cycling; mood stabilizers or antipsychotics should accompany or replace antidepressant therapy.

What are the signs and treatment of lithium toxicity?

Coarse tremor, ataxia, nausea, vomiting, confusion, and seizures with levels typically above 1.5 mEq per L; treat with IV fluids and hemodialysis for severe toxicity, levels above 4, or neurologic compromise.

What common exposures precipitate lithium toxicity?

Dehydration, NSAIDs, thiazide diuretics, ACE inhibitors, and acute kidney injury, all of which reduce renal lithium clearance.

What is the first-line treatment for acute mania?

An antipsychotic (olanzapine, risperidone, quetiapine, or haloperidol) alone or combined with lithium or valproate, with benzodiazepines as adjuncts for agitation and sleep.

What is Psychosis?

A symptom state, not a diagnosis, defined by loss of contact with reality manifesting as delusions, hallucinations, disorganized thought or speech, or grossly disorganized behavior.

What red flags suggest secondary (medical) rather than primary psychiatric psychosis?

New onset after age 40, abnormal vital signs, altered level of consciousness, focal neurologic deficits, visual, tactile, or olfactory hallucinations, sudden onset, and disorientation.

What constitutes medical clearance for a first-episode psychotic patient?

History, complete physical and neurologic exam, vital signs, glucose, CBC, BMP, urinalysis, urine drug screen, pregnancy test, and TSH, with CT head, LP, or ammonia added when focal findings, fever, or altered consciousness are present.

What is the preferred pharmacologic combination for acute undifferentiated agitation with psychosis?

Haloperidol 5 mg plus lorazepam 2 mg IM, often with diphenhydramine 50 mg to prevent dystonia, or a second-generation agent such as ziprasidone 10 to 20 mg IM.

Which antipsychotic and benzodiazepine combination should be avoided by the IM route?

IM olanzapine combined with IM benzodiazepines, because of the risk of excessive sedation, hypotension, respiratory depression, and death.

How is an acute dystonic reaction from antipsychotics treated?

Diphenhydramine 25 to 50 mg IV or IM, or benztropine 1 to 2 mg IV or IM, with resolution typically within minutes.

What is neuroleptic malignant syndrome and how is it treated?

Fever, lead-pipe rigidity, autonomic instability, altered mental status, and markedly elevated CK developing over days after antipsychotic exposure; treat with drug withdrawal, aggressive cooling and fluids, and dantrolene or bromocriptine.

What is akathisia and how does it differ from agitation?

A subjective sense of inner restlessness with inability to sit still caused by antipsychotics; it worsens with additional antipsychotic dosing and is treated with propranolol, benztropine, or a benzodiazepine.

What are Schizophrenia Spectrum and Other Psychotic Disorders?

A group of disorders defined by positive symptoms, negative symptoms, and functional decline, distinguished from one another primarily by symptom duration and the presence or absence of mood episodes.

How are the psychotic disorders distinguished by duration?

Brief psychotic disorder lasts less than 1 month, schizophreniform disorder lasts 1 to 6 months, and schizophrenia requires at least 6 months of continuous disturbance including 1 month of active symptoms.

What defines schizoaffective disorder?

Concurrent mood episode and active psychotic symptoms, plus at least 2 weeks of delusions or hallucinations occurring in the absence of a mood episode.

What are the positive versus negative symptoms of schizophrenia?

Positive symptoms are hallucinations, delusions, disorganized speech, and disorganized behavior; negative symptoms are flat affect, alogia, avolition, anhedonia, and asociality and are more treatment resistant.

What must be considered when a patient on clozapine presents to the ED with fever?

Agranulocytosis requiring an immediate absolute neutrophil count, as well as clozapine-induced myocarditis, which presents with fever, chest pain, tachycardia, and elevated troponin in the first weeks of therapy.

What ED-relevant cardiac risk do antipsychotics carry?

QT prolongation with risk of torsades de pointes, greatest with haloperidol IV, ziprasidone, and droperidol; obtain an ECG and check potassium and magnesium before repeat dosing.

Why do patients with schizophrenia have high ED mortality risk?

They have a shortened life expectancy from metabolic syndrome, cardiovascular disease, smoking, and delayed care-seeking, plus a roughly 5 percent lifetime suicide rate, so somatic complaints must not be dismissed as psychiatric.

What is Delirium?

An acute, fluctuating disturbance of attention and awareness caused by an underlying medical condition, substance, or medication, representing a medical emergency rather than a psychiatric diagnosis.

How does delirium differ from dementia?

Delirium has acute onset, fluctuating course, impaired attention, altered consciousness, and is reversible; dementia has insidious onset, stable progressive course, preserved attention early, and normal consciousness.

Which subtype of delirium is most commonly missed and carries the worse prognosis?

Hypoactive delirium, which presents with lethargy and withdrawal, is frequently mistaken for depression or fatigue, and is associated with higher mortality than hyperactive delirium.

What are the common causes of delirium in the ED?

Infection (urinary tract and pneumonia), medications (anticholinergics, benzodiazepines, opioids), electrolyte derangement, hypoglycemia, hypoxia, dehydration, urinary retention, constipation, stroke, and alcohol or sedative withdrawal.

What tool is used to formally identify delirium at the bedside?

The Confusion Assessment Method (CAM), requiring acute onset with fluctuating course plus inattention, and either disorganized thinking or altered level of consciousness.

What is the ED workup for new-onset delirium in an older adult?

Point-of-care glucose, vital signs with pulse oximetry, CBC, BMP, calcium, urinalysis and culture, ECG, chest radiograph, medication review, and CT head with LP added when trauma, focal deficits, fever, or headache are present.

How is agitated delirium managed pharmacologically?

Treat the underlying cause and use nonpharmacologic reorientation first, reserving low-dose haloperidol 0.5 to 1 mg for dangerous agitation; avoid benzodiazepines except in alcohol or sedative withdrawal, where they are first line.

Why should physical restraints and Foley catheters be minimized in delirium?

Both prolong and worsen delirium by increasing immobility, agitation, and infection risk; mobilization, hearing aids, glasses, and family presence reduce duration.

What are Somatic Symptom Disorders?

Disorders in which physical symptoms cause distress and disproportionate thoughts, feelings, or behaviors about health, with symptoms produced unconsciously and not intentionally feigned.

How does somatic symptom disorder differ from illness anxiety disorder?

Somatic symptom disorder features actual distressing physical symptoms with excessive health preoccupation, while illness anxiety disorder features preoccupation with having a serious illness with minimal or absent somatic symptoms.

How do factitious disorder and malingering differ from somatic symptom disorder?

Factitious disorder involves intentional falsification of symptoms for the internal reward of the sick role, malingering involves intentional falsification for external gain such as money, drugs, or shelter, and both differ from somatic symptom disorder, where symptoms are not consciously produced.

What is the ED approach to a patient with known somatic symptom disorder?

Validate the symptom experience, perform a focused examination, avoid repeat imaging and unnecessary testing, screen for a new organic process, and arrange consistent follow-up with a single primary care provider.

Why is somatic symptom disorder never a safe first-visit ED diagnosis?

Patients with these disorders develop organic disease at the same rate as everyone else, and anchoring on a psychiatric label is a leading source of missed diagnoses.

What legal obligation arises with factitious disorder imposed on another?

It constitutes child abuse (or elder abuse) and mandates an immediate report to child or adult protective services and separation of the child from the caregiver.

What ED red flags argue against a somatic explanation?

Abnormal vital signs, objective neurologic deficits, weight loss, nocturnal symptoms, fever, age over 50 with new symptoms, or any finding reproducible on repeat exam.

What is Functional Neurological Symptom Disorder (Conversion Disorder)?

A disorder of altered voluntary motor or sensory function that is clinically incompatible with recognized neurologic disease and is not intentionally produced, often but not always following a psychological stressor.

What positive physical signs support functional weakness?

Hoover sign (hip extension strength returns with contralateral hip flexion), give-way or collapsing weakness, tremor entrainment to a tapped rhythm, and inconsistent findings between formal testing and functional movement.

How are psychogenic nonepileptic seizures distinguished from epileptic seizures?

Nonepileptic events feature closed eyes with resistance to opening, side-to-side head shaking, pelvic thrusting, asynchronous limb movement, prolonged duration, preserved awareness, no postictal confusion, and normal lactate and prolactin.

What must be excluded before diagnosing functional neurologic disorder in the ED?

Acute stroke, which requires urgent neuroimaging and stroke pathway activation, along with spinal cord compression, Guillain-Barré syndrome, myasthenia gravis, and hypoglycemia.

Is la belle indifférence useful for diagnosis?

No; the classic apparent unconcern about a dramatic deficit is neither sensitive nor specific and should never be used to make the diagnosis.

How should the diagnosis be communicated to the patient?

As a positive, real, and common diagnosis based on specific examination findings, explaining that the nervous system is malfunctioning rather than damaged, since blaming the patient or calling it psychological worsens outcomes.

What is the treatment for functional neurologic disorder?

Physical and occupational therapy as the mainstay, with cognitive behavioral therapy, treatment of comorbid depression or anxiety, and outpatient neurology plus psychiatry follow-up.

What are Eating Disorders?

Psychiatric illnesses characterized by disturbed eating behaviors and body image distortion, principally anorexia nervosa, bulimia nervosa, and binge-eating disorder, and carrying the highest mortality of any psychiatric condition.

How are anorexia nervosa and bulimia nervosa distinguished?

Anorexia nervosa involves significantly low body weight with restriction and intense fear of weight gain, whereas bulimia nervosa involves recurrent binge eating with compensatory behaviors in a patient who is typically normal weight or overweight.

What are the life-threatening cardiac findings in eating disorders?

Bradycardia, hypotension, hypothermia, orthostasis, prolonged QTc, and ventricular arrhythmias driven by hypokalemia, hypomagnesemia, and myocardial atrophy.

What ED findings mandate medical admission in an eating disorder patient?

Heart rate below 40, systolic blood pressure below 80, temperature below 96 degrees Fahrenheit, potassium below 3, glucose below 60, arrhythmia, syncope, marked orthostasis, or severe malnutrition with hemodynamic instability.

What is refeeding syndrome?

A potentially fatal shift of phosphate, potassium, and magnesium intracellularly when nutrition is reintroduced, causing hypophosphatemia with cardiac failure, arrhythmia, respiratory failure, and seizure; prevent by starting nutrition slowly with thiamine and close electrolyte monitoring.

What physical findings suggest purging behavior?

Russell sign (knuckle calluses), parotid gland hypertrophy, dental enamel erosion, subconjunctival hemorrhage, and hypokalemic hypochloremic metabolic alkalosis.

Which medication is first-line for bulimia nervosa and which is contraindicated?

Fluoxetine is the only FDA-approved agent for bulimia nervosa; bupropion is contraindicated because of markedly increased seizure risk in purging patients.

What laboratory panel should be obtained in an ED eating disorder evaluation?

CBC, BMP with magnesium and phosphorus, liver enzymes, glucose, ECG for QTc, and pregnancy test, with TSH and amylase as indicated.

What are Sleep/Wake Disorders?

Conditions marked by disturbances in the quality, timing, or amount of sleep that impair daytime function, including insomnia disorder, obstructive sleep apnea, narcolepsy, circadian rhythm disorders, and parasomnias.

What is the ED approach to acute insomnia complaints?

Identify and treat underlying causes such as pain, substance withdrawal, depression, or sleep apnea, provide sleep hygiene counseling, and avoid discharging patients on benzodiazepines or z-drugs.

Why should diphenhydramine be avoided as a sleep aid in elderly ED patients?

Its anticholinergic burden precipitates delirium, urinary retention, falls, and worsened cognition, and it appears on the Beers criteria as potentially inappropriate.

What screening tool identifies obstructive sleep apnea risk and why does it matter in the ED?

STOP-BANG (Snoring, Tired, Observed apnea, Pressure, BMI, Age, Neck, Gender); high risk patients are prone to sedation-related respiratory depression, hypercapnic respiratory failure, difficult airway, and comorbid atrial fibrillation and pulmonary hypertension.

What is the classic tetrad of narcolepsy?

Excessive daytime sleepiness, cataplexy (sudden loss of muscle tone triggered by emotion), hypnagogic or hypnopompic hallucinations, and sleep paralysis, associated with loss of hypothalamic hypocretin (orexin) neurons.

What is the significance of REM sleep behavior disorder?

Dream enactment with loss of normal REM atonia that strongly predicts future synucleinopathy such as Parkinson disease, Lewy body dementia, or multiple system atrophy, and causes injury to the patient and bed partner.

How does sleep deprivation interact with psychiatric emergencies?

It precipitates and sustains manic episodes, worsens psychosis and suicidality, and impairs delirium recovery, making sleep restoration a therapeutic priority in the psychiatric ED patient.

What are Substance-Related Disorders?

Disorders involving problematic patterns of substance use leading to clinically significant impairment, encompassing intoxication, withdrawal, and use disorders across alcohol, opioids, stimulants, sedatives, cannabis, and hallucinogens.

What is the timeline of alcohol withdrawal?

Tremor, anxiety, and autonomic hyperactivity at 6 to 24 hours, withdrawal seizures at 12 to 48 hours, alcoholic hallucinosis with intact sensorium at 12 to 24 hours, and delirium tremens at 48 to 96 hours.

What is delirium tremens and how is it treated?

Withdrawal delirium with confusion, agitation, hallucinations, fever, tachycardia, and hypertension carrying significant mortality if untreated; treat with symptom-triggered high-dose benzodiazepines using CIWA-Ar, escalating to phenobarbital, propofol, or dexmedetomidine for refractory cases.

Why is thiamine given before glucose in the alcoholic patient?

Glucose administration in a thiamine-deficient patient can precipitate Wernicke encephalopathy, whose triad is confusion, ophthalmoplegia, and ataxia.

What is the ED management of opioid overdose and withdrawal?

Overdose is treated with naloxone titrated to adequate respirations rather than full arousal; withdrawal is not life-threatening and is quantified with COWS and treated with buprenorphine, clonidine, ondansetron, loperamide, and NSAIDs, with ED-initiated buprenorphine plus referral being the standard of care.

What is the first-line treatment for cocaine or methamphetamine toxicity with agitation and chest pain?

Benzodiazepines as the cornerstone, plus aspirin, nitroglycerin, and cooling as needed; nonselective beta-blockers are traditionally avoided due to concern for unopposed alpha stimulation.

Which withdrawal syndromes can be fatal?

Alcohol and sedative-hypnotic (benzodiazepine and barbiturate) withdrawal, both of which can cause seizures and cardiovascular collapse, in contrast to opioid withdrawal, which is miserable but rarely lethal.

What is cannabinoid hyperemesis syndrome and how is it treated?

Cyclic vomiting with abdominal pain relieved by hot showers in a chronic cannabis user; treat with topical capsaicin, haloperidol or droperidol, and fluids, since conventional antiemetics are often ineffective, with cannabis cessation being curative.

What is alcoholic ketoacidosis and how does it differ from DKA?

An anion gap metabolic acidosis from starvation and alcohol use with predominantly beta-hydroxybutyrate ketosis and normal or low glucose; treat with dextrose-containing fluids and thiamine rather than insulin.

What are Toxidromes?

Characteristic constellations of vital signs, mental status, pupils, skin, and bowel findings that identify a class of poisoning and guide empiric therapy before laboratory confirmation.

What defines the anticholinergic toxidrome and how is it treated?

Hyperthermia, mydriasis, dry flushed skin, urinary retention, absent bowel sounds, delirium, and tachycardia (hot as a hare, dry as a bone, red as a beet, blind as a bat, mad as a hatter); treat with benzodiazepines and supportive care, with physostigmine reserved for pure anticholinergic delirium without TCA involvement.

What distinguishes the sympathomimetic from the anticholinergic toxidrome?

Both cause agitation, mydriasis, tachycardia, and hyperthermia, but sympathomimetic toxicity produces diaphoresis and normal or increased bowel sounds, while anticholinergic toxicity produces dry skin and absent bowel sounds.

What defines the cholinergic toxidrome and how is it treated?

DUMBBELS (Diarrhea, Urination, Miosis, Bronchorrhea and Bronchospasm, Emesis, Lacrimation, Salivation) from organophosphates or carbamates; treat with high-dose atropine titrated to drying of secretions plus pralidoxime and aggressive decontamination.

What defines the opioid toxidrome?

Miosis, respiratory depression, and depressed mental status with bradycardia and hypothermia; treat with naloxone and airway support.

How is serotonin syndrome distinguished from neuroleptic malignant syndrome?

Serotonin syndrome develops within hours with clonus, hyperreflexia (lower extremity predominant), mydriasis, and diarrhea and is treated with benzodiazepines and cyproheptadine; NMS develops over days with lead-pipe rigidity, hyporeflexia, and marked CK elevation and is treated with dantrolene or bromocriptine.

What are the ED findings and treatment of salicylate toxicity?

Tinnitus, hyperpnea, nausea, and a mixed respiratory alkalosis with anion gap metabolic acidosis; treat with sodium bicarbonate for serum and urine alkalinization, potassium repletion, and hemodialysis for severe toxicity, altered mental status, or pulmonary edema.

What is the antidote and decision tool for acetaminophen overdose?

N-acetylcysteine, with the Rumack-Matthew nomogram applied to a 4-hour or later level after a single acute ingestion; treat empirically when timing is unknown or ingestion is staggered.