Panic disorder: epidemiology, diagnosis, and treatment in primary care.

Anxiety is the fifth most common clinical diagnosis in the primary care setting. Panic disorder, a severe episodic form of anxiety, has been found to occur in approximately 6% of primary care patients. These patients often selectively focus on one of the frightening autonomic symptoms and are frequently misdiagnosed. The three most common presentations of panic disorder in the medical setting are cardiac symptoms (chest pain, tachycardia), neurologic symptoms (headache, dizziness/vertigo, syncope), and gastrointestinal symptoms, especially epigastric distress. The presentation of cardiac symptoms by patients with panic disorder is especially likely to lead to expensive and potentially iatrogenic medical testing. Hypertension and peptic ulcer are the most commonly associated medical diagnoses in patients with panic disorder. Major depression, alcohol abuse, simple phobias, and posttraumatic stress disorder are the most frequently associated psychiatric diagnoses. Psychopharmacologic treatment of panic disorder has been demonstrated to be highly effective in double-blind, placebo-controlled studies. Effective psychopharmacologic agents include the tricyclic antidepressants (notably imipramine and desipramine), the monoamine oxidase inhibitors (phenelzine), and the high-potency benzodiazepines (alprazolam).