Clinical characteristics and response to sodium lactate of patients with infrequent panic attacks.

Nine patients with panic attacks too infrequent to meet DSM-III criteria for panic disorder were compared to 20 panic disorder patients with respect to clinical characteristics and response to sodium lactate infusion. The two groups showed similar clinical characteristics and response to lactate. The authors conclude that patients with infrequent panic attacks are clinically and biologically similar to those with panic disorder and discuss implications for the diagnosis of panic states.