Intranasal and Intravenous Oxytocin for Analgesia to Noxious Heat Pain

Description

This protocol will utilize a randomized, triple-masked, cross-over study design to compare intravenous (IV) to intranasal (IN) oxytocin administration for analgesia to an experimental pain stimulus in healthy volunteers. Equal numbers of adult men and women; ages 18-55 will be recruited. Participants will report to the research unit for three visits, 1) screening, informed consent, pregnancy test, and training to consistently rate pain from an FDA-approved device to test heat pain. The lowest temperature which causes a pain score of greater than 2 with 5 minutes of heating will be identified, 2) intravenous infusion and self-administered intranasal spray of study drug and 5-minute heat testing at intervals for 4 hours, 3) a repeat of the procedures done at visit two.

Participants will receive intravenous oxytocin, 20 IU and intranasal placebo on one of these visits and intravenous placebo and intranasal oxytocin, 48 IU, on the other. Pain score at the end of 5-minute skin heating will be compared using mathematical modeling of the time course of change in each individual and in the study population as a whole. The effect, if any, on these models of participant age, sex, and weight will be explored.