New research shows that the treatment for opioid addicts is negatively affecting their testosterone levels.
Researchers at McMaster University found men using methadone have significantly suppressed testosterone levels, and about a quarter of the testosterone of men not using opioids.
Women using methadone to treat the addiction did not see a significant impact on their testosterone levels.
Low testosterone in men has been associated with poor quality of life as well as erectile dysfunction, fatigue, and mood disturbances.