Normal urinary free cortisol and plasma MHPG in panic disorder: clinical and theoretical implications.

Abnormalities of the hypothalamic-pituitary-adrenal (HPA) axis and noradrenergic function have been reported in patients with panic disorder. Mean urinary free cortisol and plasma MHPG were measured in 12 medication-free panic disorder patients and 12 normal controls. No significant difference in urinary free cortisol and plasma MHPG was observed between the patients and controls. There was no relationship between plasma MHPG and urinary free cortisol in the panic patients or normal controls. These findings are described within the context of current concepts of stress and noradrenergic dysfunction in panic disorder.