Am J Psychiatry 1986; 143:495-502
Copyright © 1986 by American Psychiatric Association
Possible mechanisms for lactate's induction of panic
MR Liebowitz, JM Gorman, A Fyer, D Dillon, M Levitt and DF Klein
Forty-three patients with panic disorder or agoraphobia with panic attacks
and 20 control subjects received 0.5 M racemic sodium lactate intravenous
infusions, single-blind as to duration and sequence. During the procedure,
pulse; blood pressure; blood L-lactate and pyruvate; plasma ionized
calcium, phosphate, prolactin, epinephrine, norepinephrine, and cortisol
levels; and venous PCO2, pH, and bicarbonate were measured in an attempt to
clarify the mechanism of lactate-induced panic attacks. During the
infusion, 72% of the patients but none of the control subjects had panic
attacks. The laboratory findings suggest that peripheral catecholamine
surge is not the mechanism by which lactate causes panic, although elevated
epinephrine may be a predisposing factor. Heightened central noradrenergic
activity was present in many but not all of the attacks. Contrary to
previous hypotheses, neither depression of ionized calcium nor induction of
metabolic alkalosis appears sufficient to cause panic during lactate
infusion.
