Effects of Intranasal Oxytocin on Sexual Well-Being in Patients With Arginine Vasopressin Deficiency and Healthy Controls

Inclusion Criteria for healthy controls: * Adult healthy volunteers aged 18 years and above * Matched for age, sex, BMI, and menopause/hormonal contraceptives to patients * No medication, except hormonal contraception * At least mild impairment in sexual function and satisfaction, defined as an ASEX-score ≥10 points and an NSSS-S score ≤ 48 points * Only Part A: Participants must be sexually active (at least once a week sexual intercourse) and in a current partnership for at least 6 months Inclusion criteria for patients: * Adult patients aged 18 years and above, with a confirmed diagnosis of AVP deficiency based on established criteria * Stable hormone replacement therapy for at least three months with desmopressin and, in case of additional anterior pituitary deficiencies, with the respective substitution therapies * At least mild impairment in sexual function and satisfaction, defined as an ASEX-score ≥10 points and an NSSS-S score ≤ 48 points * Only Part A: Participants must be sexually active (at least once a week sexual intercourse) and in a current partnership for at least 6 months Exclusion Criteria: * Pregnancy and breastfeeding within the last eight weeks * Participation in a trial with investigational drugs within 30 days * Active substance use disorder within the last six months * Consumption of alcoholic beverages \>15 drinks/week * Current or previous psychotic disorder (e.g., schizophrenia)