Oxytocin Effects on Bone in Children With Autism Spectrum Disorder

Inclusion Criteria: 1. Ages 6 to 18 years old at Randomization 2. BMI greater than or equal to the 5th percentile 3. Expert clinical diagnosis of ASD 4. Availability of parent/guardian to provide informed consent Exclusion Criteria: 1. Fragile X, tuberous sclerosis, William's syndrome, Angelman's syndrome, Noonan syndrome, and other single gene defects that are syndromic and affect heart or bone density 2. Other conditions that may contribute to low bone density (e.g., hypogonadism) 3. Medications that may impact bone other than calcium or vitamin D supplementation, other than calcium or vitamin D supplementation, such as specific anti-seizure medications (Phenytoin, Phenobarbital), oral glucocorticoids, hormonal contraceptive injection (Medroxyprogesterone acetate (Depo-Provera) 4. Hyponatremia 5. Liver enzymes (AST, ALT, and Bilirubin) more than three times the upper limit of the normal range 6. Estimated glomerular filtration rate (eGFR) less than 60 7. Substance use disorder within the last 6 months 8. History of known coronary artery disease, heart failure, reduced ejection fraction, hypertrophic cardiomyopathy, ventricular arrhythmias, or prolonged QT (QTc greater than or equal to 480 msec) 9. Active seizures within 6 months preceding the Screening visit or the Baseline visit 10. Subjects who are pregnant, lactating, or who refuse contraception if sexually active 11. Subjects who have had previous treatment with OXT (within 2 months of Randomization) 12. Subjects who are not able to cooperate with medication administration, blood drawing, or imaging procedures despite behavior training 13. Caregivers who are unable to speak English, be consistently present at study visits to report on symptoms or, per the judgement of the data collection team, are unable to comply with the protocol 14. Any significant illness, condition, medication, or medical device that the Investigator determines could interfere with study participation and impact data collection or subject safety