Panic disorder requires recurrent unexpected panic attacks PLUS persistent worry about future attacks (or behavioral change to avoid them) for at least 1 month. The unexpectedness is diagnostic — situationally bound panic alone does not meet criteria. The disorder is the recurrent unpredictable nature plus the anticipatory worry.
A panic attack is a discrete episode of intense fear or discomfort peaking within minutes with at least 4 of 13 symptoms: palpitations, sweating, trembling, shortness of breath, choking sensation, chest pain, nausea, dizziness, chills/heat, paresthesias, derealization/depersonalization, fear of losing control, fear of dying. The cardiac and respiratory symptoms drive most ED presentations.
The self-amplifying loop (familiar from V1's panic attack scenario): amygdala fires → HPA axis activates → locus coeruleus floods cortex with NE → insula reads bodily sensation → cortex generates catastrophic interpretation ("I am dying") → interpretation feeds back to amygdala → amygdala fires harder. The loop resolves in minutes as autonomic systems normalize, but the dread remains.
Treatment combines fast and slow approaches:
Fast: benzodiazepines (alprazolam, lorazepam) provide acute relief through GABA-A enhancement within 10-20 minutes. Useful for acute attacks during SSRI titration. Problematic as chronic primary treatment.
Slow: SSRIs (sertraline, paroxetine, fluoxetine, escitalopram) and SNRIs reduce baseline amygdala reactivity over 4-8 weeks. Start low (panic patients often initially feel worse with SSRI initiation due to acute serotonergic effects) and titrate. The slow approach is what produces durable improvement.
Cognitive-behavioral therapy with interoceptive exposure is highly effective — addresses the cortical-feedback arm of the loop. The patient learns through structured practice that a racing heart or shortness of breath does not always mean a heart attack — that anxiety sensations themselves are not dangerous. This breaks the catastrophic interpretation that fuels the loop. Combined CBT + SSRI outperforms either alone and produces lower relapse rates.
Comorbidities common: agoraphobia (40-50% of panic disorder patients develop avoidance of situations where escape would be hard), depression (50%+ lifetime), substance use (often self-medication). Comprehensive assessment and treatment of comorbidities essential. When you encounter a patient with recurrent unexpected panic attacks, the treatment is well-evidenced and effective. The patient often arrives convinced they have a cardiac problem — clear diagnostic communication is part of treatment.