The study will compare Repetitive Transcranial Magnetic Stimulation (rTMS) with placebo rTMS in reducing Cocaine and/or Methamphetamine use. Study participants will be adults who currently use Cocaine and/or Methamphetamine. Eligible participants will receive multiple sessions of repetitive Transcranial Magnetic Stimulation (rTMS) or placebo rTMS over the course of an 8-week treatment period and will complete follow-up assessments for 8 weeks post-treatment. Participants will be compensated for participating.

This study is designed to evaluate the safety and effectiveness of using a combination of two different medications (extended release naltrexone and bupropion) compared to matching placebo (an inactive substance) in the treatment of methamphetamine use disorder. Participants will undergo screening, and if eligible, will receive study medications along with brief medication management for twelve weeks, with follow up visits at weeks 14 and 16. The total study duration is around 19 weeks.