Behavioral Health

Panic disorder: diagnosis and treatment

Clinical Overview and When to Suspect Panic Disorder

— A panic attack is a symptom (can occur in PTSD, social anxiety, depression, substance use, medical illness)

— Panic disorder requires the attacks to be unexpected (out of the blue) and recurrent, with anticipatory anxiety

— Lifetime prevalence ~2–5%; women 2× men

— Bimodal onset: late adolescence and mid-30s; new onset after age 45 should raise suspicion for a medical mimic

— Strong comorbidity with major depression (~50%), agoraphobia, alcohol/sedative use disorder, and other anxiety disorders

— Young adult with repeated ED visits for "heart attack" but normal troponins/ECG

— Patient reports discrete 10-minute episodes of palpitations, chest pain, dyspnea, paresthesias, derealization, fear of dying

— Avoidance of places where escape feels difficult (driving, crowds, bridges) — suggests agoraphobia overlay

— Frequent primary-care utilization, multiple negative workups, somatic preoccupation

— Dysregulated locus coeruleus noradrenergic firing, amygdala hyperreactivity, blunted GABAergic tone

— CO₂ inhalation and sodium lactate infusion provoke attacks in susceptible patients (false suffocation alarm hypothesis)

Board pearl: New-onset panic-like symptoms in a patient >45 or with abnormal vitals is NOT panic disorder until proven otherwise — work up cardiac, endocrine, and substance causes before committing to the psychiatric label. Step 3 will punish premature diagnostic closure here.

Definition: Recurrent, unexpected panic attacks plus ≥1 month of either persistent worry about additional attacks/their consequences or maladaptive behavioral change (e.g., avoidance) — DSM-5-TR criteria

Panic attack vs panic disorder:

Epidemiology:

When to suspect on Step 3:

Pathophysiology pearls:

Genetics/risk: First-degree relative with panic disorder confers 4–8× risk; childhood separation anxiety, smoking, and recent major life stressor are modifiable/contextual risks

Presentation Patterns and Key History

— Cardiopulmonary: palpitations, chest pain/tightness, shortness of breath, choking sensation

— Autonomic: sweating, trembling, chills/heat sensations, nausea, dizziness

— Neurologic: paresthesias, derealization/depersonalization

— Cognitive: fear of losing control, fear of dying, fear of "going crazy"

— Abrupt crescendo to peak in <10 minutes, typically resolves within 20–30 minutes

— Patient often presents after the attack, exhausted and frightened, with normal vitals

— Truly unexpected attacks are required for diagnosis, but situationally predisposed attacks also occur (driving, malls, elevators)

— Nocturnal panic attacks (waking from non-REM sleep in panic) occur in ~25% and strongly support the diagnosis once OSA, nocturnal arrhythmia, and GERD are excluded

— Persistent fear of recurrence, catastrophic misinterpretation of normal bodily sensations

— Avoidance behaviors → agoraphobia

— Reassurance-seeking, repeated ED visits, "checking" pulse/BP at home

— Substance use: caffeine, stimulants, cocaine, cannabis, decongestants, albuterol, levothyroxine overreplacement, SSRI initiation/withdrawal, benzodiazepine withdrawal, alcohol withdrawal

— Recent SSRI dose increase can transiently worsen panic in first 1–2 weeks

— Sleep, trauma history, suicidal ideation, prior psychiatric treatment

— Functional impairment: missed work, school, relationships, driving avoidance

Key distinction: In PTSD, attacks are cued by trauma reminders; in social anxiety, by scrutiny; in specific phobia, by the feared object. In panic disorder, at least some attacks must be uncued. Step 3 vignettes hinge on this distinction — read the trigger carefully before choosing the diagnosis.

Core attack phenomenology (need ≥4 of 13 DSM symptoms, peak within minutes):

Temporal signature:

Triggers and context:

Behavioral consequences (the "month of worry" criterion):

High-yield history to elicit:

Physical Exam Findings (and Hemodynamic Assessment when relevant)

— Tachycardia (often 100–130), tachypnea, mild hypertension, diaphoresis, tremor, cool/clammy extremities

— Hyperventilation may produce carpopedal spasm, perioral paresthesias, lightheadedness (respiratory alkalosis)

— Pupils may appear mildly dilated; bowel sounds normal

— Normal vitals, normal cardiopulmonary exam

— Patient may appear anxious, hypervigilant, or fatigued

— No focal neuro deficits, no thyroid enlargement, no exophthalmos, no tremor at rest

— Persistent tachycardia >110 between attacks → think hyperthyroidism, pheochromocytoma, SVT, stimulant use

— Sustained or paroxysmal hypertension with headache and diaphoresis → pheochromocytoma

— Focal neurologic signs, tongue bite, postictal confusion → seizure

— Wheezing, hypoxia, hemoptysis → asthma, PE

— Murmur (mid-systolic click) → mitral valve prolapse (classically associated, weakly causal)

— Goiter, lid lag, brisk reflexes → thyrotoxicosis

— Orthostatic hypotension or autonomic failure → POTS, adrenal insufficiency

— Obtain BP in both arms, orthostatics, continuous SpO₂, telemetry

— Document a rhythm strip during symptoms if feasible — single most useful real-time data point

— Glucose fingerstick (hypoglycemia mimics panic exactly)

Step 3 management: When a patient presents to the ED mid-attack, do not skip ABCs and a 12-lead ECG even when panic is clinically obvious. The board-favorite trap is the 32-year-old "panic patient" whose ECG shows WPW or whose troponin is elevated. Confirm a benign workup before psychiatric disposition.

During an active attack:

Between attacks (the typical clinic encounter):

Red flags that argue AGAINST primary panic disorder:

Hemodynamic assessment in the ED:

Diagnostic Workup — Initial Labs / Imaging / ECG / Biomarkers

— 12-lead ECG: rule out arrhythmia, ischemia, long QT (relevant before starting QT-prolonging agents like citalopram), WPW, Brugada pattern

— CBC: anemia (palpitations, dyspnea), infection

— BMP: electrolyte derangements, glucose, renal function (drug dosing)

— TSH ± free T4: hyperthyroidism is the single most important endocrine mimic; check in every new panic presentation

— Fingerstick glucose during symptoms if feasible

— Urine toxicology: cocaine, amphetamines, cannabis, PCP

— Pregnancy test (β-hCG) in women of reproductive age before any pharmacotherapy

— Troponin + chest pain pathway if cardiac features, age >40, or risk factors

— D-dimer/CT-PA if pleuritic chest pain, hypoxia, immobilization, malignancy, OCP use

— 24-hour urine metanephrines or plasma free metanephrines if paroxysmal hypertension + headache + diaphoresis (pheochromocytoma triad)

— 5-HIAA if flushing and diarrhea (carcinoid)

— Holter or event monitor for recurrent palpitations without captured rhythm

— Echocardiogram if murmur or structural concern

— Routine CT head, MRI, EEG are not indicated without focal findings, seizure features, or atypical course

— PHQ-PD and Panic Disorder Severity Scale (PDSS) track severity and response

— GAD-7 and PHQ-9 to screen for comorbid GAD and depression

Board pearl: Always check TSH and a urine drug screen before locking in panic disorder on a Step 3 vignette — these are the two most commonly tested mimics and the cheapest tests to "miss."

Panic disorder is a clinical, DSM-based diagnosis — labs serve to exclude mimics, not confirm

Recommended initial workup for a first presentation:

Targeted/second-tier testing (only if history suggests):

Imaging:

Validated screening tools (useful in primary care and Step 3 CCS framing):

Diagnostic Workup — Advanced or Confirmatory Studies

— A. Recurrent unexpected panic attacks

— B. At least one attack followed by ≥1 month of (1) persistent concern/worry about additional attacks or consequences, OR (2) significant maladaptive behavioral change

— C. Not attributable to substance/medication or another medical condition

— D. Not better explained by another mental disorder (e.g., social anxiety, PTSD, OCD, separation anxiety)

— Ambulatory cardiac monitoring (event monitor, mobile cardiac telemetry, or implantable loop recorder) when palpitations are the dominant symptom and resting ECG is normal — captures paroxysmal SVT, AVNRT, atrial fibrillation

— Tilt-table testing if syncope or presyncope with attacks → POTS, neurocardiogenic syncope

— Polysomnography if nocturnal panic with snoring, witnessed apneas, or daytime sleepiness → OSA

— EEG only if features suggest temporal lobe seizures (déjà vu, automatisms, postictal state, stereotyped semiology)

— MRI brain if focal neuro signs, new-onset after age 45, or atypical features

— Pheochromocytoma evaluation: plasma free metanephrines (high sensitivity); follow with CT/MRI adrenals if biochemistry positive

— Screen for depression (PHQ-9), GAD (GAD-7), alcohol use (AUDIT-C), suicidal ideation (C-SSRS)

Key distinction: Temporal lobe epilepsy can mimic panic with sudden fear, derealization, and autonomic symptoms — but features stereotyped semiology, postictal confusion, and impaired awareness. EEG and MRI are diagnostic; panic disorder has none of these.

There is no confirmatory test for panic disorder — diagnosis is met when DSM-5-TR criteria are satisfied AND medical/substance causes are reasonably excluded

DSM-5-TR criteria (memorize the structure):

Specifier: "With agoraphobia" if marked fear/avoidance of ≥2 of: public transport, open spaces, enclosed places, crowds/lines, being outside the home alone

Advanced workup in selected cases:

Comorbidity assessment is part of the "confirmatory" workup:

Risk Stratification or First-Line Management Logic

— Reduce panic attack frequency and severity

— Eliminate anticipatory anxiety and agoraphobic avoidance

— Restore function (work, driving, relationships)

— Treat comorbid depression, substance use

— Cognitive behavioral therapy (CBT) with interoceptive exposure and cognitive restructuring — 12–16 sessions

— SSRI or SNRI pharmacotherapy

— Combination for severe disease, comorbid depression, or partial response

— Patient preference is decisive; both have NNT ~3–4

— CBT preferred in pregnancy, breastfeeding, adolescents, patients with substance use disorder, or those refusing medication

— SSRI preferred when CBT unavailable, comorbid depression, severe symptoms limiting therapy engagement

— Combination for severe agoraphobia or partial responders at 8–12 weeks

— Step 1: Psychoeducation (panic attacks are not dangerous; symptoms are autonomic, self-limited), lifestyle (caffeine ≤200 mg/day, alcohol/cannabis cessation, sleep, aerobic exercise)

— Step 2: CBT or SSRI/SNRI

— Step 3: Switch to alternate first-line agent, add CBT, or combine

— Step 4: TCA (clomipramine, imipramine) or MAOI in refractory cases; psychiatry referral

— Not first-line for maintenance — risk of tolerance, dependence, cognitive impairment, falls, and interference with CBT extinction learning

— Short-term bridge (2–4 weeks) at SSRI initiation may be appropriate

— Avoid in elderly, substance use history, OSA

Step 3 management: When the vignette offers "alprazolam PRN" as a long-term answer for panic disorder, it is almost always wrong. The correct answer is SSRI plus CBT, with a short benzodiazepine bridge only if symptoms are disabling during the 4–6 week SSRI onset window.

Treatment goals:

First-line options (equally effective in head-to-head trials):

Choosing among first-line options — Step 3 logic:

Stepped-care framework:

Role of benzodiazepines:

Pharmacotherapy — First-Line Drug Regimen

— Sertraline: start 25 mg daily × 1 week → 50 mg; target 50–200 mg

— Escitalopram: start 5 mg → 10 mg; target 10–20 mg

— Paroxetine: start 10 mg → 20 mg; target 20–60 mg (more sedating, anticholinergic, weight gain, discontinuation syndrome — avoid in elderly and pregnancy)

— Fluoxetine: start 10 mg → 20 mg; long half-life, good for non-adherent patients

— Citalopram: max 40 mg (20 mg if >60 yo or CYP2C19 poor metabolizer) — QT prolongation, obtain baseline ECG

— Venlafaxine XR: start 37.5 mg × 1 week → 75 mg; target 75–225 mg; monitor BP (dose-dependent hypertension)

— Start LOW, go SLOW — panic patients are exquisitely sensitive to early SSRI activation (jitteriness, worsened panic in first 1–2 weeks)

— Counsel explicitly that initial worsening is expected and transient; this prevents discontinuation

— Therapeutic effect at 4–6 weeks; full response at 8–12 weeks

— Clonazepam 0.25–0.5 mg BID or lorazepam 0.5–1 mg BID for 2–4 weeks during SSRI titration

— Taper as SSRI takes effect; document a clear taper plan at the time of prescription

— Continue for at least 12 months after remission, then attempt slow taper over 2–4 months

— Many patients relapse and require long-term therapy

— If no response at adequate dose × 8–12 weeks → switch to another SSRI or SNRI

— Refractory: clomipramine or imipramine (start 10 mg, titrate); MAOIs (phenelzine) last-line

Board pearl: Bupropion is not effective for panic disorder and can worsen anxiety — high-yield distractor. Buspirone is for GAD, not panic. Both appear frequently as wrong answers.

SSRIs — first-line, all roughly equivalent in efficacy:

SNRI alternative:

Critical dosing principle in panic disorder:

Benzodiazepine bridge (selective use):

Treatment duration:

Switching/augmenting:

Procedures / Revascularization / Invasive Management (Expanded Pharmacology and Psychotherapy)

— Psychoeducation: reframing attacks as non-dangerous autonomic surges

— Cognitive restructuring: identifying and challenging catastrophic misinterpretations ("my heart is racing = I'm dying")

— Interoceptive exposure: deliberately inducing feared sensations (hyperventilation, spinning, breath-holding, straw breathing) to extinguish fear conditioning — the active ingredient unique to panic CBT

— In vivo exposure: graded reentry into avoided situations (malls, driving, elevators) for agoraphobia

— Breathing retraining and applied relaxation: adjunctive

— Typical course: 10–15 weekly sessions; effects durable 1–2+ years post-treatment

— TCAs: clomipramine, imipramine — effective but anticholinergic, orthostasis, cardiotoxicity in overdose; obtain ECG, avoid in elderly and cardiac disease

— MAOIs: phenelzine — effective but tyramine dietary restrictions, serotonin syndrome risk; specialist use only

— Mirtazapine: option when SSRIs fail or sleep is prominent issue

— Gabapentin, pregabalin: modest evidence; useful in comorbid substance use disorder where benzodiazepines are contraindicated

— Propranolol: not effective for panic disorder (helps performance anxiety only) — common distractor

— Avoid chronic benzodiazepine monotherapy

— Avoid as-needed benzodiazepines that reinforce avoidance and safety behaviors (undermines exposure)

— Avoid antipsychotics as first- or second-line

— Internet-delivered CBT (iCBT) with therapist support is effective and increasingly USPSTF/AAFP-endorsed for access-limited patients

CCS pearl: In CCS cases, order "CBT referral" alongside the SSRI on the initial orders screen. Schedule follow-up at 2 weeks (tolerability), 6 weeks (early efficacy), and 12 weeks (full response assessment). Advancing the clock without these visits costs points.

CBT for panic disorder — the procedural equivalent:

Second-line and adjunctive pharmacotherapy:

What NOT to do:

Digital and stepped delivery:

Special Populations — Elderly and Renal/Hepatic Impairment

— Panic disorder onset after age 45 is uncommon — work up medical mimics aggressively (cardiac arrhythmia, COPD, hyperthyroidism, pheochromocytoma, medication side effects, early dementia with anxiety)

— Polypharmacy and anticholinergic burden are key issues

— Avoid paroxysmal/paroxetine (anticholinergic, sedating, falls)

— Avoid TCAs (orthostasis, arrhythmia, cognitive impairment, Beers list)

— Avoid chronic benzodiazepines (Beers — falls, fractures, delirium, MVAs)

— Citalopram capped at 20 mg/day if >60 (QT risk)

— Preferred: sertraline or escitalopram, start at half the usual dose, titrate slowly

— SSRIs increase fall, fracture, hyponatremia (SIADH), and GI bleed risk (especially with NSAIDs, anticoagulants) — check sodium at 2 and 4 weeks

— SSRIs are largely hepatically metabolized; modest dose reduction generally sufficient

— Venlafaxine: reduce dose 25–50% if CrCl <30; avoid in severe renal failure

— Paroxetine and citalopram: reduce dose

— Gabapentin/pregabalin: require renal dose adjustment

— Monitor for SSRI-induced hyponatremia, especially with thiazides

— All SSRIs require dose reduction in moderate-severe hepatic impairment (start at 50% dose, titrate slowly)

— Avoid duloxetine in significant hepatic disease or chronic alcohol use (hepatotoxicity)

— Sertraline and escitalopram are generally preferred

— Paroxetine and fluoxetine are strong CYP2D6 inhibitors → tamoxifen, metoprolol, codeine, opioids

— Citalopram + other QT-prolonging agents (ondansetron, methadone, macrolides, fluoroquinolones)

— SSRI + tramadol, linezolid, MAOIs → serotonin syndrome

Board pearl: In an elderly patient on a thiazide who develops confusion 2 weeks after starting sertraline, check serum sodium — SSRI-induced SIADH is a classic Step 3 vignette and missed diagnosis cause of delirium.

Elderly (>65) considerations:

Renal impairment:

Hepatic impairment:

Drug-interaction screening in elderly:

Special Populations — Pregnancy, Pediatrics, and Perinatal

— Untreated panic disorder is associated with preterm birth, low birth weight, and postpartum exacerbation — untreated illness has real risks

— CBT is first-line in mild–moderate disease; preferred over pharmacotherapy

— If medication needed: sertraline is the most evidence-supported SSRI in pregnancy (low placental transfer, extensive safety data)

— Avoid paroxetine — associated with cardiac malformations (especially in first trimester); FDA pregnancy category D historically

— Late third-trimester SSRI use: neonatal adaptation syndrome (jitteriness, feeding difficulty, transient tachypnea) and small absolute risk of persistent pulmonary hypertension of the newborn (PPHN) — do not abruptly discontinue in third trimester; balance risks

— Benzodiazepines: avoid in first trimester (cleft palate concern, mixed data) and near delivery (floppy infant syndrome, neonatal withdrawal)

— Sertraline and paroxetine have lowest milk transfer and are preferred for nursing mothers

— Monitor infant for sedation, poor feeding, irritability

— Screen with EPDS; panic disorder commonly first emerges or worsens postpartum

— Coordinate with obstetrics and pediatrics; involve partner/family supports

— Panic disorder is uncommon before puberty; rule out medical causes (asthma, arrhythmia, hyperthyroidism, substance use)

— CBT is first-line for children and adolescents

— If SSRI needed: fluoxetine and sertraline have most pediatric evidence

— Black box warning: SSRIs increase suicidal ideation in patients <25 — counsel patient/family, schedule weekly follow-up × 4 weeks, then biweekly

— Involve parents in safety planning, lethal means restriction

Step 3 management: A pregnant patient with disabling panic disorder who fails CBT should be offered sertraline, not "wait until after delivery." Withholding effective treatment for untreated maternal anxiety carries its own fetal and neonatal risk.

Pregnancy:

Breastfeeding:

Postpartum:

Pediatrics and adolescents:

Complications and Adverse Outcomes

— Agoraphobia: progressive avoidance leading to housebound state in severe cases

— Major depressive disorder: comorbid in ~50%; doubles suicide risk

— Suicide: panic disorder independently increases suicide attempt risk (~2–3×), especially with comorbid depression or substance use — screen at every visit

— Substance use disorders: self-medication with alcohol, benzodiazepines, cannabis, opioids

— Occupational and social impairment: job loss, relationship dysfunction, financial strain

— Increased healthcare utilization: repeated ED visits, unnecessary cardiac and GI workups — driver of cost and iatrogenic harm

— Cardiovascular: modest independent association with coronary events, possibly via sympathetic tone and behavioral risk factors

— SSRI initiation: transient activation, increased anxiety/jitteriness in first 1–2 weeks (counsel preemptively to prevent discontinuation)

— SSRI sexual dysfunction: decreased libido, anorgasmia, delayed ejaculation — major cause of nonadherence; manageable by dose reduction, switch to bupropion (for comorbid depression, not panic itself), or PDE5 inhibitor

— SSRI discontinuation syndrome: flu-like symptoms, dizziness, "brain zaps," irritability — worst with paroxetine and venlafaxine (short half-lives); taper over 4+ weeks

— Serotonin syndrome: triad of mental status change, autonomic instability, neuromuscular hyperactivity (clonus, hyperreflexia) — risk with tramadol, linezolid, MAOIs, triptans, MDMA

— Hyponatremia (SIADH): elderly, thiazide co-use; check Na at 2 and 4 weeks in at-risk patients

— Bleeding: SSRI + NSAID or anticoagulant increases GI bleed risk — co-prescribe PPI when needed

— QT prolongation: citalopram, escitalopram (less)

— Benzodiazepine complications: dependence, withdrawal seizures, falls, MVAs, respiratory depression with opioids (FDA black box)

Key distinction: Serotonin syndrome (hyperreflexia, clonus, rapid onset) vs neuroleptic malignant syndrome (rigidity, hyporeflexia, slower onset). Both feature hyperthermia and autonomic instability — exam differentiator is the neuromuscular exam.

Disease-related complications:

Treatment-related adverse outcomes:

When to Escalate Care — Psychiatry Consult, Inpatient Triage

— Treatment failure: no response after 2 adequate SSRI trials (8–12 weeks each at therapeutic dose)

— Severe agoraphobia preventing daily function

— Significant comorbidity: bipolar disorder, psychosis, severe substance use disorder, eating disorder

— Diagnostic uncertainty

— Need for TCA or MAOI therapy

— Pregnancy with severe symptoms requiring complex risk-benefit discussion

— Active suicidal ideation with plan or intent

— Recent suicide attempt

— Inability to care for self

— Severe comorbid depression with psychotic features

— Acute substance intoxication or withdrawal complicating presentation

— Severe benzodiazepine or alcohol withdrawal requires inpatient detoxification with monitored taper (CIWA, phenobarbital protocols)

— Suspected medical mimic (e.g., pheochromocytoma, unstable arrhythmia) warrants medical admission for workup

— Primary care typically manages uncomplicated panic disorder with SSRI + CBT referral

— Collaborative care models (embedded behavioral health in primary care) improve outcomes and are increasingly the value-based standard

— Document a clear safety plan and crisis resources (988 Suicide & Crisis Lifeline) at every visit

— After ED evaluation for panic attack, ensure outpatient follow-up within 1–2 weeks, written discharge instructions, and warm handoff to primary care or behavioral health when possible

— Failure to arrange follow-up is a common patient-safety gap and Step 3 exam target

CCS pearl: For a patient discharged from the ED after a panic-related visit, the order set should include: PCP follow-up within 1 week, behavioral health referral, written 988 crisis information, and counseling on caffeine/alcohol/stimulant avoidance. Missing the follow-up order costs CCS points.

Outpatient management is appropriate for the vast majority — panic disorder rarely requires hospitalization

Indications for urgent psychiatry referral (outpatient):

Indications for emergency department/inpatient psychiatric admission:

Medical admission considerations:

Care coordination:

Transitions of care:

Key Differentials — Same-Category Causes (Other Psychiatric Conditions)

— Chronic, pervasive worry across multiple domains for ≥6 months

— No discrete attacks with abrupt onset; somatic symptoms (muscle tension, sleep disturbance, irritability) dominate

— May coexist with panic disorder

— Attacks triggered specifically by social/performance scrutiny

— Persistent fear of negative evaluation

— Attacks cued by specific object/situation (heights, blood, flying)

— No unexpected attacks

— Attacks triggered by trauma reminders

— Re-experiencing, avoidance, negative cognitions/mood, hyperarousal

— Trauma history is the diagnostic anchor

— Anxiety driven by obsessions, relieved temporarily by compulsions

— Discrete unexpected attacks are uncommon

— Same symptom domains as PTSD but within 1 month of trauma; lasting 3 days to 1 month

— Identifiable psychosocial stressor within 3 months; symptoms not meeting criteria for panic disorder

— Preoccupation with having illness, with minimal or no actual somatic symptoms (illness anxiety) or with disproportionate response to real symptoms (somatic symptom)

— Overlap with panic exists; high healthcare utilization in both

— Depression with prominent anxiety/restlessness; mood symptoms dominate

— Screen for prior manic/hypomanic episodes before starting SSRI — antidepressants can precipitate mania; missed bipolar diagnosis is a Step 3 favorite

Key distinction: The trigger pattern of attacks is the diagnostic key. Truly unexpected attacks = panic disorder. Cued attacks (social, traumatic, phobic, obsessional) = the corresponding disorder. Read the vignette for the cue before answering.

Generalized anxiety disorder (GAD):

Social anxiety disorder:

Specific phobia:

PTSD:

OCD:

Acute stress disorder:

Adjustment disorder with anxiety:

Illness anxiety disorder (formerly hypochondriasis) and somatic symptom disorder:

Major depressive disorder with anxious distress:

Bipolar disorder:

Key Differentials — Other-Category Causes (Medical Mimics)

— Paroxysmal SVT, AVNRT, atrial fibrillation: sudden palpitations with anxiety as secondary response; capture rhythm during symptoms — event monitor is the test

— WPW: delta wave on resting ECG; risk of preexcited AF

— Mitral valve prolapse: classic association, modest causal link

— Acute coronary syndrome: especially in women, elderly, diabetics with atypical presentations

— Pulmonary embolism: acute dyspnea, pleuritic chest pain, hypoxia, sinus tachycardia — never miss in a young woman on OCPs

— Asthma exacerbation: wheeze, prolonged expiratory phase, peak flow drop

— Hyperventilation alone is a symptom, not a diagnosis — find the cause

— Hyperthyroidism: weight loss, heat intolerance, tremor, tachycardia, lid lag — TSH is the screen

— Pheochromocytoma: paroxysmal hypertension, headache, palpitations, diaphoresis ("the 4 P's"); plasma free metanephrines

— Carcinoid syndrome: flushing, diarrhea, wheezing; urine 5-HIAA

— Hypoglycemia: fingerstick during symptoms; sulfonylureas, insulin, insulinoma

— Adrenal insufficiency, Cushing syndrome: rarer mimics

— Temporal lobe (complex partial) seizures: stereotyped fear, derealization, automatisms, postictal state

— Vestibular disorders: vertigo misinterpreted as dizziness/panic

— Migraine with aura

— Intoxication: cocaine, amphetamines, MDMA, cannabis, caffeine, decongestants, albuterol overuse, levothyroxine excess, theophylline

— Withdrawal: alcohol, benzodiazepines, opioids, SSRIs

— Anaphylaxis (early, before urticaria), mastocytosis

Board pearl: Pheochromocytoma, hyperthyroidism, and pulmonary embolism are the three "never miss" medical mimics on Step 3 panic vignettes. Each has a specific test: plasma metanephrines, TSH, and CT-PA respectively.

Cardiac:

Pulmonary:

Endocrine:

Neurologic:

Substance/medication:

Other:

Secondary Prevention / Discharge Medications / Long-Term Plan

— Continue effective SSRI/SNRI for at least 12 months after full remission

— Higher relapse risk: prior recurrences, severe baseline symptoms, comorbid depression, residual symptoms — these patients may require indefinite treatment

— Taper over 2–4 months minimum when discontinuing; faster tapers risk discontinuation syndrome and relapse

— Booster CBT sessions every few months can prevent relapse

— Continued self-directed exposure homework

— Caffeine ≤200 mg/day (some patients eliminate entirely)

— Avoid recreational stimulants and cannabis

— Limit alcohol (≤1 drink/day women, ≤2 men) — alcohol is a common self-medication that worsens long-term anxiety

— Regular aerobic exercise (150 min/week moderate intensity) — independently anxiolytic

— Sleep hygiene: 7–9 hours, consistent schedule; treat OSA if present

— Mindfulness-based stress reduction: adjunctive evidence

— Smoking cessation: nicotine and withdrawal both provoke panic

— Treat comorbid depression, substance use, OSA — each worsens panic if untreated

— Coordinate care with primary care, behavioral health, and any subspecialists

— Personal "panic plan": breathing technique, cognitive reframe, exposure homework

— Identify and rehearse what to do during an attack (stay, ride it out, do not flee)

— Avoid safety behaviors (carrying unused benzodiazepines as a talisman, avoiding driving)

— Return of anticipatory anxiety, new avoidance, sleep disruption, increased caffeine/alcohol use → re-engage CBT, consider dose increase

Step 3 management: When a patient in remission for 6 months asks to stop their SSRI, the correct counsel is to continue for at least 12 months total, then taper slowly over 2–4 months while continuing CBT skills. Premature discontinuation is the single biggest preventable cause of relapse.

Maintenance pharmacotherapy:

Maintenance psychotherapy:

Lifestyle prescription:

Comorbidity management:

Patient self-management toolkit:

Relapse warning signs:

Follow-Up, Monitoring Parameters, and Rehab/Counseling

— 2 weeks after SSRI initiation: tolerability, activation, suicidal ideation (especially if <25), adherence

— 4–6 weeks: early efficacy, dose titration if partial response

— 8–12 weeks: assess for full response; switch or augment if inadequate

— Every 3 months during maintenance: symptoms, function, side effects, comorbidity screening

— Annually in stable patients: reassess need for continued therapy, screen depression/substance use

— All SSRIs: mood, suicidal ideation, sexual function, GI symptoms, sleep

— Citalopram/escitalopram: baseline and follow-up ECG if cardiac risk or other QT-prolonging drugs

— Venlafaxine: blood pressure at each visit (dose-dependent hypertension)

— Elderly on SSRI + diuretic: serum sodium at 2 and 4 weeks

— SSRI + NSAID/anticoagulant: monitor for bleeding; consider PPI

— Benzodiazepine (if used short-term): document indication, plan for taper, screen for misuse with PDMP review

— PDSS (Panic Disorder Severity Scale): track at baseline, 4, 8, 12 weeks

— PHQ-9, GAD-7: monitor comorbid depression and generalized anxiety

— Functional measures: work attendance, driving, social engagement

— Set realistic expectations: 4–6 weeks for SSRI onset; CBT requires active homework

— Normalize transient activation in first 2 weeks

— Explain that PRN benzodiazepines undermine extinction learning

— Discuss sexual side effects proactively — improves adherence

— Provide written safety plan and 988 crisis line at every visit

— Graduated return to avoided activities (driving, work, public transport) — often coordinated with CBT therapist

CCS pearl: Always schedule the 2-week follow-up visit when starting an SSRI in a CCS case — it captures activation, early suicidal ideation, and tolerability. Skipping it is a recurrent point deduction pattern.

Standard follow-up cadence (Step 3 longitudinal voice):

Monitoring parameters by medication:

Outcome measures:

Counseling pearls:

Rehabilitation:

Ethical, Legal, and Patient Safety Considerations

— Disclose black-box warning of increased suicidal ideation in patients <25

— Discuss sexual dysfunction, discontinuation syndrome, and pregnancy considerations in reproductive-age patients

— Document the conversation; provide written materials when feasible

— Parental consent + adolescent assent for SSRI initiation

— Confidentiality protections vary by state; suicidal ideation generally overrides confidentiality

— Disclosure of intent to harm an identifiable third party triggers Tarasoff duty to warn/protect (jurisdiction-dependent)

— Suspected child or elder abuse during evaluation → mandatory report

— Severe agoraphobia or sedating medications (benzodiazepines, certain TCAs) may impair driving — counsel and document

— Commercial drivers, pilots, and safety-sensitive workers may have profession-specific reporting requirements; coordinate with occupational medicine

— Check PDMP before prescribing benzodiazepines

— Avoid co-prescribing benzodiazepines with opioids (FDA black box: respiratory depression, fatal overdose)

— Document indication, duration, and taper plan for every benzodiazepine prescription

— Patients discharged from the ED after a "panic attack" have elevated short-term risk of missed medical diagnosis and of suicide

— Always: confirm normal workup, schedule outpatient follow-up within 1–2 weeks, provide written instructions and crisis line, perform warm handoff to behavioral health when possible

— Verify the patient understands return precautions: new neurologic symptoms, syncope, chest pain with exertion, suicidal ideation

— Panic disorder rarely impairs decisional capacity; refusal of medication must be respected with continued offer of CBT and re-engagement

— Panic disorder is underrecognized in minoritized populations and frequently misattributed to "noncardiac chest pain" without follow-up referral; ensure equitable access to CBT and culturally appropriate care

Board pearl: A patient who reports homicidal ideation toward a named individual during a panic disorder visit triggers Tarasoff duty. The correct exam answer is to warn the identifiable victim and notify law enforcement — not simply documenting and continuing routine care.

Informed consent for SSRI therapy:

Pediatric/adolescent consent and assent:

Mandatory reporting and duty to protect:

Driving and occupational safety:

Controlled substance stewardship:

Transition-of-care risk (high-yield Step 3 patient safety theme):

Capacity and treatment refusal:

Health equity:

High-Yield Associations and Rapid-Fire Clinical Facts

Key distinction: Panic attack is a symptom present in many disorders; panic disorder requires unexpected, recurrent attacks plus ≥1 month of worry or behavioral change. Master this distinction — it appears on nearly every Step 3 anxiety vignette.

Comorbidity is the rule, not the exception: ~50% MDD, 25% substance use disorder, common GAD/social anxiety overlap

Female:male ratio 2:1; bimodal onset late teens and mid-30s

Mitral valve prolapse — classically associated, weakly causal; do not anchor on it

Childhood separation anxiety predicts adult panic disorder

Smoking is associated with onset and severity of panic disorder — smoking cessation is therapeutic

CO₂ inhalation (35%) and sodium lactate infusion provoke attacks in patients with panic disorder — false suffocation alarm hypothesis

Nocturnal panic attacks in ~25%; arise from non-REM sleep, distinct from nightmares (REM) and night terrors (slow-wave, children)

First-line drug = SSRI; first-line therapy = CBT with interoceptive exposure

Sertraline and escitalopram = generally preferred SSRIs (tolerability, drug interactions, pregnancy data for sertraline)

Paroxetine = avoid in elderly (anticholinergic), pregnancy (teratogenic), and patients sensitive to discontinuation syndrome

Citalopram = QT prolongation; max 40 mg (20 mg if >60)

Venlafaxine = monitor BP

Bupropion, buspirone, propranolol = NOT first-line for panic disorder (common distractors)

Benzodiazepines = bridge only, not maintenance; avoid in elderly, OSA, substance use, with opioids

Treatment duration: ≥12 months after remission; taper slowly

SSRI activation in first 1–2 weeks — preempt with counseling; start low, go slow

Discontinuation syndrome worst with paroxetine and venlafaxine

Serotonin syndrome: clonus, hyperreflexia, autonomic instability, mental status change — distinguishes from NMS (rigidity, hyporeflexia)

SIADH: elderly + thiazide + SSRI — check Na at 2 and 4 weeks

Pheo, hyperthyroidism, PE = three "never miss" medical mimics

TSH and urine tox = cheapest, highest-yield mimic screen

Tarasoff = duty to warn identifiable victim

988 = US Suicide & Crisis Lifeline — document on every discharge

Board Question Stem Patterns

— 28-year-old woman, third ED visit in 6 months for chest pain and palpitations; ECG, troponins, D-dimer normal each time

— Answer: Start SSRI (sertraline), refer to CBT, schedule PCP follow-up in 2 weeks

— Trap: "Alprazolam PRN" as the long-term plan

— 48-year-old with new "panic attacks," episodes of severe headache, BP 220/120 during episodes, diaphoresis

— Answer: Plasma free metanephrines (pheochromocytoma), not SSRI

— Patient started on sertraline 5 days ago, now worse anxiety and jitteriness

— Answer: Counsel that this is transient activation, continue medication, consider short benzodiazepine bridge; do not stop the SSRI

— 72-year-old on HCTZ starts paroxetine; 2 weeks later, confused, Na 124

— Answer: Discontinue paroxetine (SSRI-induced SIADH), fluid restrict, switch agent if needed

— Patient started on SSRI for "panic," develops decreased sleep, grandiosity, hypersexuality

— Answer: Discontinue SSRI; reassess for bipolar disorder; mood stabilizer

— Pregnant patient with disabling panic disorder failing CBT

— Answer: Sertraline (not paroxetine); shared decision-making, monitor for neonatal adaptation

— Patient on chronic alprazolam now requests increase; PDMP shows multiple prescribers

— Answer: Initiate slow taper, start SSRI + CBT, address substance use disorder

— Patient with panic disorder discloses plan to harm named ex-partner

— Answer: Warn the identifiable victim and notify law enforcement

— Patient stops paroxetine abruptly, develops dizziness, brain zaps, flu-like symptoms

— Answer: Reinstate and taper slowly

Step 3 management: When in doubt on a panic vignette, the answer is almost always SSRI + CBT + appropriate follow-up. The exam rewards comprehensive, longitudinal management over single interventions.

Pattern 1 — The repeat ED visitor:

Pattern 2 — The medical mimic:

Pattern 3 — The activation effect:

Pattern 4 — The elderly hyponatremia:

Pattern 5 — The bipolar unmasking:

Pattern 6 — Pregnancy:

Pattern 7 — The benzodiazepine misadventure:

Pattern 8 — Tarasoff:

Pattern 9 — Discontinuation syndrome:

One-Line Recap

Panic disorder is recurrent unexpected panic attacks plus ≥1 month of anticipatory worry or maladaptive behavioral change, diagnosed clinically after exclusion of medical and substance mimics, and treated first-line with an SSRI (sertraline or escitalopram) plus CBT with interoceptive exposure, continued at least 12 months after remission with structured follow-up.

— Unexpected, recurrent attacks (≥4 of 13 symptoms, peak <10 min) + ≥1 month of worry/behavioral change

— Always exclude TSH abnormalities, substances, arrhythmia, pheochromocytoma, PE, hypoglycemia

— Onset >45 or atypical features → medical workup before psychiatric label

— First-line: SSRI + CBT (equally effective; combine for severe disease)

— Start LOW, go SLOW; counsel about transient activation

— Avoid paroxetine in elderly/pregnancy; cap citalopram at 20 mg if >60

— Benzodiazepines are a short bridge only — never maintenance

— Bupropion, buspirone, propranolol are NOT effective for panic disorder

— Follow-up at 2, 6, and 12 weeks; assess PDSS, suicidal ideation, side effects

— Maintain ≥12 months after remission; taper slowly over 2–4 months

— Lifestyle: caffeine ≤200 mg/day, no stimulants, limit alcohol, aerobic exercise, sleep hygiene

— Treat comorbid depression, substance use, OSA

— Screen suicide at every visit; provide 988 lifeline

— Tarasoff duty applies to identifiable threats

— Coordinate ED-to-outpatient transitions within 1–2 weeks

— Collaborative care in primary care improves outcomes

Board pearl: The single most testable concept is that chronic benzodiazepine monotherapy is the wrong answer — SSRI plus CBT with appropriate follow-up is the right answer in nearly every Step 3 panic disorder vignette.

Diagnosis:

Treatment:

Longitudinal management (Step 3 emphasis):

Safety and systems: