Inclusion Criteria:

• * Central diabetes insipidus (based on routine clinical practice, e.g., clinical symptoms, serum and urinary sodium and osmolality levels or the water deprivation test)
• * Normal FT4 or T4
• * Stable hormone replacement (no change in dose of hormone replacement in six weeks prior to baseline)

Exclusion Criteria:

• * Active substance use disorder within the last 6 months
• * History of psychosis
• * Current suicidal ideation
• * Medication changes within 4 weeks of enrollment or during the study
• * History of cardiac disease, including arrhythmias, coronary heart disease, coronary artery spasms, valvular heart disease, hypertrophic cardiomyopathy (hypertension is not exclusionary)
• * Hyponatremia
• * Creatinine \>1.5mg/dL.
• * ALT or AST \>2.5x upper limit of normal
• * Hematocrit less than 2% below the norm
• * Pregnancy or breastfeeding within the last 8 weeks
• * Unwilling to use a medically acceptable form of contraception throughout the study period (female of child-bearing potential only)
• * Received an investigational drug or medical device in the past 30 days or within 5 half-lives of main study visit or be concurrently enrolled in another investigational product clinical trial.
• * Any significant illness or condition that the Investigator determines could interfere with study participation, data collection, or safety