Participants will be eligible for participation if the following inclusion criteria are met:  at least 18 years of age have moderate tic severity or greater as evidenced by a YGTSS Total Tic Score greater than 14 (>9 for adults with motor or vocal tics only) exhibit a tic frequency of at least one visible tic per minute be fluent in English have a total premonitory urge for tics scale (PUTS) total score greater than 17 at Visit 2 have a total DTS score greater than 30 at Visit 2  Exclusion criteria for participants include:  history of cardiovascular disorder history of fainting or seizures history of frostbite open cut or sore on hand to be immersed fracture to the limb to be immersed history of Reynaud's phenomenon inability to complete rating scales inability to attend study visits