[Skip to Navigation]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address Please contact the publisher to request reinstatement.
January 1988

Carbon Dioxide—Induced Anxiety: Behavioral, Physiologic, and Biochemical Effects of Carbon Dioxide in Patients With Panic Disorders and Healthy Subjects

Author Affiliations

From the Clinical Neuroscience Research Unit, Connecticut Mental Health Center, and the Department of Psychiatry, Yale University School of Medicine, New Haven.

Arch Gen Psychiatry. 1988;45(1):43-52. doi:10.1001/archpsyc.1988.01800250051007

• Carbon dioxide was administered for 15 minutes to patients with panic disorders (5% CO2, n =14) and healthy subjects (5% CO2, n =11; 7.5% CO2, n = 8). Following administration of CO2 and air placebo, changes in behavioral ratings, vital signs, and plasma levels of the norepinephrine metabolite 3-methoxy-4-hydroxyphenylglycol, cortisol, growth hormone, and prolactin were measured over three hours. In the healthy subjects, CO2 produced dose-related increases in anxiety, somatic symptoms, vital signs, and plasma cortisol levels. In the patients, the frequency of panic attacks (in eight of 14 patients) and the increases in anxiety and somatic symptoms induced by 5% CO2 exceeded those in the healthy subjects and were similar to those induced by 7.5% CO2 in the healthy subjects. The physiologic and biochemical measurements obtained did not elucidate the mechanisms underlying CO2-induced anxiety or the greater anxiogenic effects of CO2 seen in patients with panic disorders.