Intranasal and Intravenous Oxytocin for Analgesia to Noxious Heat Pain

The goal of this research study is to find out how well oxytocin works to reduce pain. Oxytocin will be given intravenously (IV) and as a nasal spray. The study team also hopes to find out if the participants age, weight, or sex effects how well the study drug works. Participants will be exposed to a heater on the skin at a training visit and rate how much pain different temperatures cause. On two separate visits, participants will use a nasal spray and get an IV infusion. After the IV and nasal spray, participants will rate the pain of the same skin heating temperature at various time points for 4 hours.