Am J Psychiatry 1995; 152:619-622
Copyright © 1995 by American Psychiatric Association
Persistence of blunted human growth hormone response to clonidine in fluoxetine-treated patients with panic disorder
JD Coplan, LA Papp, J Martinez, D Pine, LA Rosenblum, T Cooper, MR Liebowitz and JM Gorman
College of Physicians and Surgeons of Columbia University, New York, NY 10032.
OBJECTIVE: The authors determined the effects of antipanic treatment with
fluoxetine on human growth hormone (GH) response to the alpha 2 agonist
clonidine. METHOD: Seventeen patients with panic disorder and 15 healthy
volunteers were challenged with clonidine. Thirteen of the patients and 12
of the volunteers were given a second challenge with clonidine 12 weeks
later. The patients received open fluoxetine and the healthy subjects
received no treatment between challenges. Subjects with high baseline human
GH levels (greater than 2 ng/ml) at the first and second challenges were
excluded from further analysis. RESULTS: The patients with panic disorder
(N = 13 for the first challenge and N = 9 for the second) had significantly
lower human GH responses to clonidine than the healthy subjects (N = 14
during the first challenge and N = 9 for the second) during both
challenges, despite clinical improvement in eight of the nine patients at
the time of the second challenge. CONCLUSIONS: Blunted secretion of human
GH in response to clonidine in patients with panic disorder persists
despite clinical recovery.
