Oxytocin (OXT) deficiency is increasingly recognized as a potential pituitary disorder in patients with arginine vasopressin (AVP) deficiency, formerly known as central diabetes insipidus. Vasopressin is vital for renal water reabsorption, and its inadequate secretion leads to polyuria and polydipsia. However, despite stable treatment, patients often suffer from persisting psychological symptoms such as heightened anxiety, difficulties in social interaction, reduced empathy, and decreased sexual desire, significantly affecting their quality of life.

OXT plays a crucial role in regulating complex social, emotional, and behavioral functions. Due to the anatomical proximity, local disruptions of the AVP system could also disturb OXT function, leading to an additional OXT deficiency. Since baseline OXT measurements and standard pituitary provocation tests are not reliable, our research group recently investigated MDMA as a stimulation test and revealed a significantly lower increase in OXT levels and an absence of OXT-induced effects compared to healthy controls. These results could provide a strong explanation for the observed psychopathology in these patients. However, the therapeutic potential of OXT replacement in AVP-deficient patients remains unexplored.

Our three ongoing randomized, placebo-controlled, double-blind clinical trials aim to investigate the potential benefits of intranasal OXT on anxiety, emotion recognition, social stress regulation and sexual well-being in AVP-deficient patients. Our results could, for the first time, lead to a new therapeutic approach improving psychological symptoms in these patients and thus enhancing their quality of life.