Legally protected marijuana dispensaries (LMDs) were associated with lower rates of dependence on prescription opioids, and deaths due to opioid overdose, than would have been expected based on prior trends. However, LMDs also were associated with higher rates of recreational marijuana use and increased potency of illegal marijuana.
A brain imaging study strongly suggests that regular users of marijuana have smaller orbitofrontal cortex (OFC) volumes. Such a deficit could make it more difficult to change counterproductive behaviors, including drug use.
September 2017 In a clinical trial, N-acetylcysteine did not help adults reduce their cannabis use, despite having been effective for adolescents in a previous trial. The results indicated that if adults are able to benefit from the medication, they will likely require a different treatment regimen than adolescents.
Researchers used the statistical technique of latent class analysis to describe distinct patterns of marijuana use across age using data from nearly 10,000 participants in the Monitoring the Future study. Longer-term marijuana use (extending from age 18 into the late 20s or beyond) was associated with increased risk of self-reported health problems at age 50.
Some teens' marijuana use has been linked to disrupted communication between two key regions in the brain’s reward circuitry at age 20. Disrupted communication between the regions was associated with poorer psychosocial functioning at age 22.
People with cannabis dependence have changes in neural circuitry in brain regions related to reward processing, habit formation, and psychopathology. These changes in neural circuitry may provide a useful marker for tracking psychopathology associated with cannabis misuse.
These findings add to research showing that nicotine and cannabis have interactive effects on brain structure and function. They also suggest that specialized treatment interventions may be appropriate for people who use both drugs.