Prolactin but not ACTH increases during sodium lactate-induced panic attacks.

Paradoxically, the pituitary-adrenal axis is not activated during sodium lactate-induced panic. We measured the response of another stress-sensitive hormone, prolactin, to standard lactate and placebo infusion in a double-blind randomised design in eight patients with panic disorder and eight matched normal controls. Prolactin release was significantly elevated (P < 0.05) in panickers compared with non-panickers, whereas ACTH secretion was not activated at all. This differential stress response needs further investigation.