Background: Prader-Willi syndrome (PWS) is known for hyperphagia with impaired satiety and a specific behavioural phenotype with stubbornness, temper tantrums, manipulative and controlling behaviour and obsessive-compulsive features. PWS is associated with hypothalamic and oxytocinergic dysfunction. In humans without PWS, intranasal oxytocin administration had positive effects on social and eating behaviour, and weight balance. Objective and hypotheses: To evaluate the effects of intranasal oxytocin compared to placebo administration on social behaviour and hyperphagia in children with PWS. Design: Randomized, double-blind, placebo-controlled, crossover study in a PWS Reference Center in the Netherlands. Method: Crossover intervention with twice daily intranasal oxytocin (dose range 24-48 IU/day) and placebo administration, both during 4 weeks, in 25 children with PWS (aged 6 to 14 years). Results: In the total group, no significant effects of oxytocin on social behaviour or hyperphagia were found, but in the 17 children younger than 11 years, parents reported significantly less anger (P = 0·001), sadness (P = 0·005), conflicts (P = 0·010) and food-related behaviour (P = 0·011), and improvement of social behaviour (P = 0·018) during oxytocin treatment compared with placebo. In the eight children older than 11 years, the items happiness (P = 0·039), anger (P = 0·042) and sadness (P = 0·042) were negatively influenced by oxytocin treatment compared to placebo. There were no side effects or adverse events. Conclusions: This randomized, double-blind, placebo-controlled study suggests that intranasal oxytocin administration has beneficial effects on social behaviour and food-related behaviour in children with PWS younger than 11 years of age, but not in those older than 11 years of age.,
Clinical Endocrinology
Erasmus MC: University Medical Center Rotterdam

Kuppens, R., Donze, S., & Hokken-Koelega, A. (2016). Promising effects of oxytocin on social and food-related behaviour in young children with Prader-Willi syndrome: A randomized, double-blind, controlled crossover trial. Clinical Endocrinology, 85(6), 979–987. doi:10.1111/cen.13169