Effects of 1-desamo-8-D-arginine vasopressin on behaviour and cognition in primary affective disorder.

DDAVP (1-desamino-8-d-arginine vasopressin), a synthetic analogue of vasopressin with prolonged half-life and high antidiuretic and low pressor activity, was given in a double-blind placebo-controlled trial to four patients with major affective illness. Three of four patients showed highly significant and consistent improvements in tests designed to measure the formation, encoding, and organisation of long-term trace events in memory. Two patients also showed a significant but less consistent amelioration of other depressive symptoms during DDAVP treatment. These findings implicate central vasopressin function in the processing of information and possibly other aspects of affective illness.