Anxiety Disorders, Personality Pathology & Substance Withdrawal

Memorize the diagnostic duration thresholds and first-line treatments across the anxiety and trauma spectrum: (1) Panic Disorder requires recurrent, unexpected (unprovoked) Panic Attacks—abrupt surges of intense fear reaching a peak within 10 minutes with ≥4 of 13 autonomic/cognitive symptoms (palpitations, diaphoresis, trembling, dyspnea, chest pain, paresthesias, derealization, fear of dying/going crazy)—followed by ≥1 MONTH of persistent worry about having additional attacks or maladaptive avoidance behavior (frequently coexisting with Agoraphobia: fear of being in ≥2 situations [public transit, open spaces, enclosed shops, crowds, or outside the home alone] where escape might be difficult). Note that acute panic attacks are aborted with short-term Benzodiazepines (alprazolam/lorazepam), whereas long-term first-line maintenance therapy is an SSRI/SNRI + Cognitive-Behavioral Therapy (CBT)! (2) Generalized Anxiety Disorder (GAD) requires excessive, difficult-to-control worry about multiple everyday domains (finances, work, health, family) occurring more days than not for ≥6 MONTHS, accompanied by ≥3 of 6 somatic symptoms (restlessness, easy fatigability, difficulty concentrating, irritability, muscle tension, sleep disturbance; only ≥1 required in children); treat with First-Line SSRIs (escitalopram/sertraline), SNRIs (venlafaxine/duloxetine), or Buspirone (a 5-HT_1A partial agonist that takes 2–4 weeks to work, causes zero sedation/addiction/withdrawal, and does NOT interact with alcohol!). (3) Social Anxiety Disorder (fear of scrutiny/humiliation in social interactions for ≥6 months) is treated with SSRIs/CBT for generalized disease, or Low-Dose Propranolol (beta-blocker) 30–60 minutes prior to the event for Performance-Only Social Anxiety (stage fright)! (4) Trauma-Related Disorders following exposure to actual or threatened death, serious injury, or sexual violence (featuring intrusion symptoms, avoidance, negative mood/cognition, and hyperarousal/startle) are separated strictly by the 1-Month Cutoff: Acute Stress Disorder lasts 3 days to 1 month after the trauma (treated with trauma-focused CBT), whereas Post-Traumatic Stress Disorder (PTSD) lasts >1 MONTH (treated with trauma-focused CBT/EMDR + SSRIs/SNRIs, plus the alpha-1 antagonist Prazosin specifically for trauma-related nightmares!). Contrast PTSD with Adjustment Disorder, which occurs within 3 months of a non-life-threatening psychosocial stressor (divorce, job loss, moving) and resolves within 6 months after the stressor ends.

Master the three DSM-5-TR Personality Disorder Clusters (ego-syntonic, inflexible lifelong traits beginning by early adulthood): Cluster A ('Weird' / Odd-Eccentric — Accusatory, Aloof, Awkward): Paranoid (pervasive distrust and suspicion of others' motives without fixed psychotic delusions), Schizoid (voluntary social detachment, prefers solitude, restricted emotional expression, indifferent to praise/criticism—content being alone!), and Schizotypal (eccentric behavior, odd magical thinking/superstitions, ideas of reference, and social anxiety—desires relationships but fears them due to paranoia). Cluster B ('Wild' / Dramatic-Emotional-Erratic — Bad, Borderline, Flamboyant, Must-be-best): Antisocial (pervasive disregard for and violation of the rights of others, criminality, deceitfulness, lack of remorse; CANNOT be diagnosed until Age ≥18 years, and requires evidence of Conduct Disorder BEFORE Age 15!), Borderline (frantic efforts to avoid abandonment, unstable interpersonal relationships alternating between idealization and devaluation ['Splitting' defense mechanism!], chronic feelings of emptiness, impulsivity, and recurrent suicidal/self-mutilating cutting behavior—First-Line Treatment is Dialectical Behavior Therapy [DBT]!), Histrionic (excessive emotionality and attention-seeking, sexually seductive/provocative, shallow shifting emotions), and Narcissistic (grandiose sense of self-importance, need for admiration, lack of empathy, fragile self-esteem reacting with rage to criticism). Cluster C ('Worried' / Anxious-Fearful — Cowardly, Clingy, Compulsive): Avoidant (hypersensitive to rejection/criticism, feelings of inadequacy, avoids social interaction despite desiring relationships!), Dependent (submissive, clingy need to be taken care of, fears separation), and Obsessive-Compulsive Personality Disorder (OCPD) (pervasive preoccupation with orderliness, perfectionism, rules, and control that is EGO-SYNTONIC [the patient believes their rigid perfectionism is right and normal!]—contrast with Obsessive-Compulsive Disorder [OCD], which features intrusive, anxiety-provoking, EGO-DYSTONIC Obsessions and repetitive neutralizing Compulsions, treated with Exposure and Response Prevention [ERP] CBT + High-Dose SSRIs or the tricyclic Clomipramine!).

Chronic ethanol consumption enhances inhibitory GABA_A receptor chloride influx while upregulating excitatory NMDA glutamate receptors; abrupt cessation leaves NMDA glutamate excitation completely unopposed, driving a strict 4-stage chronological withdrawal timeline that is tested on every board exam: (1) Stage 1 — Mild Autonomic Withdrawal (6 to 24 hours after last drink): anxiety, insomnia, diaphoresis, tachycardia, hypertension, GI upset, and coarse hand tremors (patient has an intact sensorium). (2) Stage 2 — Alcoholic Hallucinosis (12 to 48 hours): transient visual, tactile ('formication'—bugs crawling on skin), or auditory hallucinations with INTACT ORIENTATION and stable vital signs (this is what separates Alcoholic Hallucinosis from Delirium Tremens!). (3) Stage 3 — Alcohol Withdrawal Seizures (12 to 48 hours): generalized tonic-clonic seizures (single or brief cluster). (4) Stage 4 — Delirium Tremens (DTs, 48 to 96 hours [2–4 days] after last drink; 5%–15% mortality!): defined by the onset of global DELIRIUM (disorientation, confusion, agitation), severe autonomic instability (fever, malignant tachycardia/hypertension, drenching diaphoresis), and visual/tactile hallucinations. First-line treatment for ALL stages of alcohol withdrawal is a Symptom-Triggered (CIWA-Ar) Long-Acting Benzodiazepine (Chlordiazepoxide or Diazepam)—EXCEPT in patients with advanced Cirrhosis / Liver Failure or the Elderly, where you MUST use a 'LOT' Benzodiazepine (Lorazepam, Oxazepam, or Temazepam) because LOT benzodiazepines undergo direct Phase II glucuronidation without Phase I CYP450 oxidation or active metabolites! Finally, never forget the #1 Emergency Department Resuscitation Rule in Alcoholism: always administer Intravenous Thiamine (Vitamin B1) BEFORE or concomitantly with Dextrose (Glucose)! Infusing glucose first consumes the patient's last trace of thiamine pyrophosphate cofactor (for pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase), precipitating acute Wernicke Encephalopathy (triad: Confusion, Ophthalmoplegia/Nystagmus [CN VI palsy], and Truncal Ataxia; reversible with IV thiamine) and irreversible Korsakoff Syndrome (bilateral mammillary body and anterior/mediodorsal thalamic hemorrhage/necrosis causing permanent anterograde/retrograde amnesia with Confabulation!). Long-term alcohol relapse prevention uses Naltrexone (μ-opioid antagonist reducing cravings; contraindicated in acute hepatitis or opioid use), Acamprosate (NMDA modulator safe in liver disease; avoid in severe renal failure CrCl <30), or Disulfiram (aldehyde dehydrogenase inhibitor).

Compare the toxidromes and treatments of Opioids, Stimulants, and Hallucinogens: (1) Opioid Intoxication & Withdrawal: acute opioid overdose (heroin, fentanyl, oxycodone, methadone) produces the classic Triad: Coma/CNS Depression, Pinpoint Pupils (Miosis; exception: Meperidine causes normal/dilated pupils and seizures via normeperidine!), and Respiratory Depression (decreased respiratory rate is the #1 predictor of mortality, caused by blunted medullary chemoreceptor sensitivity to CO₂), accompanied by bradycardia, hypotension, hypothermia, and decreased bowel sounds—treated immediately with airway support and IV/Intranasal Naloxone (competitive μ-opioid antagonist with a short 30–60 minute half-life, so repeat dosing is often required for long-acting methadone/fentanyl overdoses!). Conversely, Opioid Withdrawal is intensely uncomfortable ('flu-like') but NEVER life-threatening in adults (exception: life-threatening in Neonatal Abstinence Syndrome, which presents with high-pitched crying, jitteriness, sneezing, Tachypnea, diarrhea, and seizures, treated with Oral Morphine or Methadone!), presenting with Mydriasis (dilated pupils), Rhinorrhea, Lacrimation, Yawning, Piloerection ('gooseflesh / cold turkey'), Myalgias/Arthralgias, Abdominal Cramps, Nausea/Vomiting, Diarrhea, and Tachycardia/Hypertension. Treat acute opioid withdrawal symptomatically with Clonidine or Lofexidine (central α₂-agonists reducing locus coeruleus sympathetic outflow) plus antiemetics/loperamide, and treat Opioid Use Disorder long-term with Medication-Assisted Treatment (reduces mortality by >50%!): Buprenorphine-Naloxone (Suboxone: partial μ-opioid agonist that must be started only when the patient is already in mild-to-moderate withdrawal to avoid precipitating acute withdrawal!) OR Methadone (full μ-opioid agonist; watch for QT prolongation!). (2) Stimulants & Hallucinogens: Cocaine (blocks presynaptic DAT/NET/SERT reuptake) and Amphetamines (displace vesicular catecholamines and block reuptake) cause agitation, paranoia, mydriasis, diaphoresis, tachycardia, hypertension, angina, and nasal septum perforation (cocaine) or bruxism/meth-mouth (methamphetamine)—treat acute agitation and hypertension with IV Benzodiazepines (and phentolamine/nitrates; avoid pure beta-blockers!). Phencyclidine (PCP, 'Angel Dust') is an NMDA glutamate receptor antagonist that uniquely causes violent belligerence, superhuman strength with complete insensitivity to pain, dissociative psychosis, hypertension/tachycardia, and pathognomonic ROTARY (VERTICAL AND HORIZONTAL) NYSTAGMUS (treat with a quiet room and Benzodiazepines or Haloperidol). Cannabis Intoxication presents with conjunctival injection (red eyes), increased appetite ('munchies'), dry mouth, tachycardia, and slowed time perception (chronic heavy use causes Cannabinoid Hyperemesis Syndrome: cyclic intractable vomiting uniquely relieved by compulsive hot showers and topical capsaicin!).

Unconscious psychological defense mechanisms managed by the ego are heavily tested alongside personality disorders: Mature Defenses (Sublimation, Altruism, Humor, Suppression): Sublimation channels unacceptable drives into socially constructive outlets (an aggressive teenager becomes a championship rugby player), while Suppression is the conscious, intentional postponement of anxiety-provoking thoughts (contrast with Repression, which is unconscious blocking of thoughts). Neurotic Defenses: Displacement (yelling at a spouse or kicking the dog after being berated by the attending physician), Reaction Formation (transforming an unacceptable impulse into its exact opposite, such as someone harboring unconscious resentment toward a colleague acting overly syrupy and complimentary), Isolation of Affect (describing a horrific trauma in cold, detached clinical detail without emotion), and Undoing (compulsive handwashing to 'cancel out' an intrusive thought). Immature Defenses: Splitting (Borderline PD), Projection (Paranoid PD), Passive-Aggression, and Regression (a 6-year-old resumes bedwetting and thumb-sucking when a newborn sibling arrives).

Post-Traumatic Stress Disorder (PTSD — intrusion, avoidance, negative alterations in mood/cognition, and hyperarousal persisting >1 month; versus Acute Stress Disorder if lasting 3 days to 1 month) often co-occurs with Borderline Personality Disorder and Substance Use Disorders. First-line treatment combines trauma-focused CBT (prolonged exposure, EMDR) with SSRIs (sertraline, paroxetine) or SNRIs (venlafaxine), plus the α₁-antagonist Prazosin specifically for trauma-related nightmares.

When a hospitalized patient with Borderline Personality Disorder exhibits splitting—praising the physician as 'the only competent doctor in this hospital' while demanding that the 'cruel, incompetent' nursing staff be fired—the correct management is to validate the patient's emotional distress while maintaining clear, consistent boundaries, avoiding taking sides, and holding regular multidisciplinary team meetings so all staff communicate a unified treatment plan. When a patient with Narcissistic Personality Disorder demeans a resident's credentials and demands the department chair, acknowledge the patient's desire for the highest quality care without becoming defensive.

During prolonged starvation in Anorexia Nervosa, basal insulin secretion is suppressed while glucagon and cortisol maintain euglycemia via lipolysis and ketogenesis; total body stores of intracellular electrolytes (phosphate, potassium, magnesium) and thiamine become severely depleted even though serum concentrations may appear deceptively normal. When rapid carbohydrate refeeding is initiated, the sudden glucose load triggers a massive pancreatic insulin surge. Insulin stimulates cellular glucose uptake, glycolysis (consuming inorganic phosphate to synthesize ATP and 2,3-BPG), and the Na⁺/K⁺-ATPase pump—driving phosphate, potassium, and magnesium rapidly into cells while promoting renal sodium and water retention. The resulting profound hypophosphatemia (<1.5 mg/dL) causes myocardial ATP depletion, ventricular arrhythmias, acute decompensated heart failure, diaphragmatic respiratory failure, rhabdomyolysis, hemolysis, and seizures. Prevention requires starting nutrition gradually (1,200–1,400 kcal/day), administering prophylactic thiamine, and monitoring/repleting serum phosphate, potassium, and magnesium daily.

Cardiac complications (arrhythmias and sudden cardiac death from QT prolongation, myocardial atrophy, or electrolyte derangements) and suicide are the two leading causes of mortality in Anorexia Nervosa. Immediate inpatient medical stabilization is mandatory when any of the following instability criteria are present: severe bradycardia (heart rate <40–50 bpm daytime or <45 bpm at night), hypotension (<80–90/50 mmHg), orthostatic pulse increase >20 bpm or BP drop >10–20 mmHg, hypothermia (<35.5°C / 96°F), severe electrolyte abnormalities (hypokalemia, hypophosphatemia), QTc prolongation, or weight <75% of ideal body weight (BMI <15 kg/m²).

In Anorexia Nervosa and the Female Athlete Triad (low energy availability, functional hypothalamic amenorrhea, and low bone mineral density), GnRH suppression leads to hypoestrogenemia, uncoupled osteoclast resorption, and high cortisol, causing rapid, irreversible loss of trabecular bone density and stress fractures. Crucially, oral contraceptive pills (OCPs) DO NOT restore bone mineral density in anorexia nervosa (and may falsely reassure patient and clinician by inducing artificial withdrawal bleeds); the ONLY effective treatment to rebuild bone density is weight restoration and resumption of spontaneous ovulatory menses supplemented with calcium and vitamin D.

A favorite NBOME and NBME clinical distinction compares a patient 36 hours after his last drink who sees bugs crawling on the wall (formication) or hears voices, yet is fully alert, oriented to person, place, and time, and has stable vital signs (Alcoholic Hallucinosis) versus a patient 72 hours after his last drink who is globally confused, disoriented, severely agitated, febrile (39.1°C), tachycardic (140 bpm), and diaphoretic (Delirium Tremens). The presence of delirium (waxing-and-waning sensorium/disorientation) plus severe autonomic instability defines Delirium Tremens, which carries a 5–15% mortality rate and requires ICU admission and aggressive symptom-triggered IV benzodiazepines (lorazepam or diazepam).

For patients ready to quit smoking, combining behavioral counseling with pharmacotherapy doubles abstinence rates. The single most effective pharmacologic agent for smoking cessation is Varenicline (a partial agonist at α₄β₂ nicotinic acetylcholine receptors that stimulates dopamine release to prevent cravings/withdrawal while competitively blocking nicotine from binding; safe in stable psychiatric patients, monitor for vivid dreams/nausea). Second-line options include Combined Nicotine Replacement Therapy (NRT)—pairing a long-acting transdermal nicotine patch (basal level) with a short-acting nicotine gum, lozenge, or inhaler (breakthrough cravings)—and oral Bupropion (an norepinephrine-dopamine reuptake inhibitor that also prevents post-cessation weight gain; contraindicated in seizure or eating disorders!).

Because Buprenorphine is a partial μ-opioid receptor agonist with extremely high binding affinity but lower intrinsic efficacy than full agonists (heroin, fentanyl, methadone), administering buprenorphine while a patient still has full opioid agonists bound to their μ-receptors displaces the full agonist and instantly triggers severe precipitated opioid withdrawal. Therefore, clinicians must always wait until the patient is exhibiting objective signs of mild-to-moderate opioid withdrawal (Clinical Opiate Withdrawal Scale [COWS] score ≥8–12) before administering the first induction dose of buprenorphine-naloxone.

Three nocturnal episodes are tested side-by-side on psychiatric and neurology boards: (1) A 6-year-old boy sits bolt upright 90 minutes after falling asleep (first third of the night = Stage N3 slow-wave sleep), screams in terror with dilated pupils, diaphoresis, and tachycardia, cannot be consoled by his parents, returns to sleep, and has zero recall (amnesia) of the event the next morning → Sleep Terror Disorder. (2) A 7-year-old girl awakens crying at 4:30 AM (last third of the night = REM sleep), runs to her parents' room, and describes in vivid detail a monster chasing her → Nightmare Disorder. (3) A 68-year-old man punches his wife in the face at 4:00 AM while dreaming that he is fighting off an intruder and remembers the dream upon waking → REM Sleep Behavior Disorder (early clinical marker of Parkinson disease or Dementia with Lewy Bodies).

Dissociative Disorders represent unconscious disruptions in the normal integration of consciousness, memory, identity, or perception following overwhelming psychological trauma: (1) Dissociative Identity Disorder (formerly multiple personality disorder; strongly linked to severe childhood physical/sexual abuse) features ≥2 distinct personality states accompanied by recurrent gaps in autobiographical memory for everyday events (missing time, finding unfamiliar items in one's closet). (2) Dissociative Amnesia presents with an inability to recall important autobiographical information (usually of a traumatic nature) too extensive to be ordinary forgetfulness; when accompanied by sudden, unexpected purposeful travel away from home with confusion about personal identity, it is specified as with Dissociative Fugue (contrast with Transient Global Amnesia, a neurological disorder in older adults featuring a 4–24 hour loss of anterograde memory with preserved personal identity!). (3) Depersonalization/Derealization Disorder features persistent feelings of detachment from one's body ('watching myself from outside my body') or feeling that the external world is unreal/dreamlike, while reality testing remains completely intact.

Polysomnography in patients with Major Depressive Disorder (MDD) demonstrates characteristic alterations in sleep architecture that are frequently tested on Step 1/Level 1: DECREASED REM sleep latency (entering REM in <45–60 minutes instead of the normal 90 minutes), INCREASED total REM sleep time and REM density (especially in the early part of the night), DECREASED Stage N3 slow-wave delta sleep, and frequent terminal insomnia (early-morning awakenings). Normal physiological aging similarly decreases both Stage N3 slow-wave sleep and total REM sleep while increasing sleep fragmentation.

Anorexia Nervosa is defined by restriction of energy intake leading to a significantly low body weight (BMI <18.5 kg/m2), intense fear of weight gain, and distorted body image (accompanied by lanugo hair, hypothermia, bradycardia, osteoporosis, and GnRH-deficient secondary amenorrhea; refeeding requires close phosphorus/potassium/magnesium monitoring to prevent fatal refeeding syndrome). By contrast, patients with Bulimia Nervosa maintain a normal or elevated body weight (BMI ≥18.5 kg/m2) with recurrent binge eating and compensatory purging (causing dorsal knuckle calluses [Russell's sign], bilateral parotid gland sialadenosis, lingual dental enamel erosion, and hypochloremic hypokalemic metabolic alkalosis; treated with CBT and fluoxetine; bupropion is strictly contraindicated in both anorexia and bulimia due to seizure risk!). Binge-Eating Disorder features recurrent distressful binges without compensatory purging (treated with CBT, SSRIs, or lisdexamfetamine). In somatic/deception differentials: Somatic Symptom Disorder (excessive anxiety over ≥1 persistent physical symptom) and Illness Anxiety Disorder (high health preoccupation with minimal/no somatic symptoms) involve unconscious symptom production and unconscious motivation; Factitious Disorder (Munchausen syndrome) involves conscious, intentional falsification/induction of illness driven by an unconscious psychological motivation to assume the “sick role” (primary gain) without external material reward; and Malingering involves conscious fabrication/exaggeration of symptoms driven by conscious external incentives (secondary gain: financial compensation, avoiding work/jail, or obtaining opioids).