Addressing the most compelling cannabis concern, its abuse by young people, the best meta-analysis of the data [2] reveals that even the heaviest non-medical cannabis usage in teen- agers and young adults reduces cognitive sequelae to non- statistical salience after abstinence of 72 hours with no evident permanent sequelae. No formal study has shown cognitive impairment in medical cannabis patients, and some have even documented improvement.
Recent data on efficacy of cannabis in pain management is compelling. A large prospective study in Canada (N1⁄41,145) employing approved cannabis preparations from one government-licensed manufacturer is illustrative [3], 68% of whom had chronic pain. A mean of less than one gram of can- nabis flower was consumed daily, at a stable rate over time, without evidence of tolerance, tachyphylaxis or dose escalation. At baseline 28.1% were using opioids, declining to 11.3% over the course (P<.001), with mean morphine equivalent daily dose plummeting from 152 to 32.2mg, a 78% reduction. Declines were noted in usage of other pain adjuncts. Patient quality of life measures increased in four domains with physical health up 36% and psychological 17%.