In addition, potential crossover of OXT to vasopressin receptors is of concern given that the weight loss effects of intranasal OXT are seen at supraphysiologic doses, raising the possibility of cardiovascular effects (e.g., tachycardia and heart failure via vasopressin receptor 1a [V1aR]), hyponatremia (via vasopressin receptor 2 [V2R]) [12], and, upon potential CNS exposure, anxiety and aggression in at risk patients (V1aR, vasopressin receptor 1b [V1bR]) [13,14,15]. This evidence concerns the gene AVPR1A and Hyponatremia.