A 32-year-old woman from Delhi presents to the psychiatry outpatient clinic with a 2-year history of sudden, unexpected episodes of intense fear accompanied by palpitations, sweating, trembling, and a sense of impending doom. Each episode lasts 15–20 minutes and resolves spontaneously. She reports that the attacks occur unpredictably—sometimes while at home, sometimes in public—and she has begun avoiding crowded places and public transport out of fear of having an attack. She denies any specific trigger for the panic attacks. On examination, vital signs during a calm state are normal; mental status examination reveals anxiety but no psychotic features. What is the most likely diagnosis?

Explanation

## Diagnosis: Panic Disorder without Agoraphobia ### Key Clinical Features **Key Point:** Panic Disorder is characterized by recurrent, unexpected panic attacks followed by persistent concern about future attacks or their consequences. This patient presents with the hallmark triad of panic disorder: 1. **Recurrent unexpected panic attacks** — episodes of sudden, intense fear with autonomic symptoms (palpitations, sweating, trembling) 2. **Anticipatory anxiety** — persistent worry about having another attack or its consequences 3. **Behavioral avoidance** — she has begun avoiding public places and transport to prevent panic The absence of a specific trigger distinguishes this from phobias, where anxiety is cued by a particular object or situation. ### Diagnostic Criteria (DSM-5) | Feature | Panic Disorder | GAD | Specific Phobia | Social Anxiety | |---------|---|---|---|---| | **Attack pattern** | Sudden, unexpected | Persistent, diffuse | Cued by specific stimulus | Cued by social situations | | **Duration of episode** | 10–20 minutes | Chronic (≥6 months) | Variable | Variable | | **Trigger** | Unpredictable | Multiple life domains | Specific object/situation | Social evaluation | | **Avoidance** | Secondary (fear of attack) | Minimal | Primary (of phobic object) | Primary (of social settings) | **High-Yield:** The **unpredictability** of attacks is the cardinal feature that distinguishes panic disorder from phobias (which are cued) and GAD (which is persistent and diffuse). ### Why This Patient Has Panic Disorder, Not Agoraphobia **Clinical Pearl:** Agoraphobia is diagnosed when the patient fears being in situations from which escape is difficult or embarrassing, or where help is unavailable during a panic attack. This patient avoids crowds and transport *because she fears having a panic attack*, not because she fears the situation itself. This is **secondary avoidance** — avoidance of situations where panic might occur — which is characteristic of Panic Disorder without Agoraphobia. ### Pathophysiology **Key Point:** Panic Disorder involves dysregulation of the amygdala and prefrontal cortex, with heightened interoceptive awareness (misinterpretation of normal bodily sensations as threatening). ### Management Approach 1. **First-line pharmacotherapy:** SSRIs (sertraline, paroxetine, escitalopram) or SNRIs (venlafaxine) 2. **First-line psychotherapy:** Cognitive-Behavioral Therapy (CBT) with exposure and interoceptive exposure 3. **Acute management:** Benzodiazepines for short-term symptom relief (not first-line maintenance) **Mnemonic — Panic Disorder Red Flags: SUDDEN** - **S**udden onset (no cue) - **U**nexpected episodes - **D**uration 10–20 min - **D**ysautonomia (palpitations, sweating, tremor) - **E**scaped from situation (avoidance behavior) - **N**o specific phobic object - **D**read of recurrence (anticipatory anxiety)