Inflammation in Methamphetamine and STIs (IMSTI)

This clinical trial aims to investigate the effects of a decline in methamphetamine use on rectal inflammatory cytokine levels, substance use contexts, and HIV/STI risk behavior. This clinical trial also seeks to evaluate joint effects of methamphetamine use and rectal gonorrhea/chlamydia infection on rectal inflammatory cytokine levels. The proposed trial will consist of 40 MSM, half with rectal gonorrhea/chlamydia infection at enrollment (n=20), with methamphetamine use disorder that will receive contingency management for methamphetamine reduction. Following baseline measurement, participants will be observed over the course of 8 weeks, where participants will complete behavioral surveys, provide urine for drug testing, and rectal samples for measurement of rectal inflammatory cytokine levels.