Am J Psychiatry 1990; 147:462-464
Copyright © 1990 by American Psychiatric Association
Plasma concentrations of melatonin in panic disorder
IM McIntyre, FK Judd, GD Burrows, SM Armstrong and TR Norman
Department of Psychiatry, University of Melbourne, Austin Hospital, Heidelberg, Victoria, Australia.
Nocturnal plasma melatonin concentrations were measured in seven patients
with panic disorder and eight healthy control subjects. The five patients
who had never received psychotropic medication had significantly greater
melatonin concentrations from 4:00 a.m. to 7:00 a.m. than the control
subjects. In addition it is possible that a phase delay occurred in these
unmedicated patients. The findings are discussed in terms of previous
studies showing increased melatonin in manic patients and the effect of
intense stress on melatonin synthesis. The two patients who had been
medication free for only 1 week showed a decreased melatonin rhythm, which
is consistent with previous findings in medicated patients.
