Panic disorder is intense fear with multiple somatic symptoms (palpitations, etc).
“Panic disorder typically presents in late adolescence or early adulthood with unpredictable episodes of palpitations, sweating, gastrointestinal distress, dizziness, and paresthesias. The attacks are sporadic and last 10–60 minutes. Generalized anxiety disorder is more common, and common symptoms include restlessness, fatigue, muscle tension, irritability, difficulty concentrating, and sleep disturbance.
Pheochromocytoma is associated with headache and hypertension, and usually occurs in thin patients. Paroxysmal supraventricular tachycardia is usually not associated with gastrointestinal distress or paresthesias. While mitral valve prolapse can be associated with anxiety and panic disorder, the physical examination would not be normal.” ABFM
Reference
Kasper DL, Fauci AS, Hauser SL, et al (eds): Harrison’s Principles of Internal Medicine, ed 19. McGraw-Hill, 2015, pp 2708-2709.