Discrimination between panic disorder and generalized anxiety disorder by 35% carbon dioxide challenge.

Abstract

The authors' goal was to determine whether 35% carbon dioxide (CO2) challenge would discriminate between patients with panic disorder and patients with other anxiety disorders. Nine patients with panic disorder and nine with generalized anxiety disorder underwent the 35% CO2 challenge. Patients with panic disorder experienced a significantly stronger increase in subjective anxiety than patients with generalized anxiety disorder. However, increases in panic symptom scores were high in both groups. These results suggest that a large increase in subjective anxiety due to the CO2 challenge is specific for patients with panic disorder but that an increase in panic symptoms is not.