By: Robert G. Bell
And you thought the smoke had cleared and it was safe to go back in the water….
In a previous post, I felt Colorado and Washington (and now Oregon and Alaska) were embarking on one of the world’s largest, uncontrolled, observational clinical studies regarding the safety, use, and abuse of cannabis, and that answers regarding marijuana’s safety, especially fetal and adolescent development, dosage, formulations, quality, drug-drug interactions, and abuse were needed. Although it has only been a couple of years, what do the real world observations of recreational and medicinal use of cannabis tell us regarding the safety, efficacy, and abuse of this drug? Enquiring minds still want to know, so consider this an interim analysis without compromising the alpha level!
At the recent NIH Neuroscience Summit on Marijuana and Cannabinoids, the neurological and psychiatric effects, adverse events, and the potential therapeutic effects of cannabis and the cannabinoid system were discussed. The summit tried to address many of the safety, efficacy, and abuse questions that have been raised, and some of the summary highlights are listed below.
- Regarding the marijuana use and the adolescent brain, marijuana adversely influences learning; memory and attention also can show mild long-term effects. These outcomes improve with days to weeks of abstinence. The effect of marijuana on cognition appears worse with earlier age of onset.
- There is an association between exposure to cannabinoids and various psychotic outcomes, including the development of schizophrenia.
- Cannabis has addictive potential (cannabis use disorder), resembling other substance use disorders, and that addiction may be increasing. The factors that influence the probability of cannabis use disorder are similar to those that affect other substance use disorders.
- Regarding pediatric epilepsy, cannabidiol (CBD) has shown activity against seizures in some preclinical models, and there is initial evidence suggesting that CBD may reduce seizures in some children with refractory epilepsy. However, there is evidence of multiple adverse effects of CBD and other marijuana products, including potential long-term cognitive and behavioral effects.
- Regarding multiple sclerosis, cannabinoids seem to be effective at controlling specific cardinal symptoms of multiple sclerosis—spasticity and central pain—as indicated by several high-quality randomized controlled trials, but THC/oral cannabinoids seem to be ineffective at controlling tremor and bladder symptoms in multiple sclerosis.
- Regarding pain, cannabinoid CB2 agonists show promise for suppressing pathological pain without the unwanted side effects of CB1. Cannabis demonstrates efficacy in the treatment of neuropathic pain and has a reasonably acute safety profile.
Since Colorado serves as the nation’s hub of our experimental marijuana observational clinical study, the Rocky Mountain High Intensity Drug Trafficking Area Program (RMHIDTA) has put out numerous reports on the impact of the legalization of marijuana for medical and recreational use in Colorado. Some significant trends are starting to emerge:
- From 2010 to 14, Colorado marijuana-related traffic deaths increased 92%; during the same time period all traffic deaths only increased 8%.
- In 2014, when retail marijuana businesses began operating, there was a 29% increase in the number of marijuana-related emergency room visits and a 38% increase in the number of marijuana-related hospitalizations in only one year.
- In the two-year average (2013/2014) since Colorado legalized recreational marijuana, use in youths, young adults, and adults have increased significantly:
- Youth (ages 12–17) marijuana use ranked #1 in the nation for past month marijuana use, up from #4 in 2011/2012, an increase of 20% compared to the two-year average prior to legalization, and was 74% higher than the national average compared to 39% higher in 2011/2012. Nationally, youth marijuana use declined 4% during the same time.
- Marijuana-related exposures among young children (ages 0–5 years) in Colorado had a 138% increase (31 per year) from the medical marijuana commercialization years (2009–2012) average, which was a 225% increase from pre-commercialization years (2006–2008).
- College age (ages 18–25) marijuana use increased 17% compared to the two-year average prior to legalization. The national college age marijuana use increased 2% during the same time.
- Adult marijuana use ranked #1 in the nation, up from #7 in 2011/2012, and Colorado marijuana use for 2013/2014 was 104% higher than the national average compared to 51% higher in 2011/2012. Adult marijuana use increased 63% compared to the two-year average prior to legalization whereas the national adult marijuana use increased 21 percent during the same time.
The reports generated by NIH and RMHIDTA are telling and describe the potential for great therapeutic hope as well as the tragedy of abuse associated with the medicinal and recreational use of marijuana. The apparent increased trends regarding traffic fatalities, hospitalizations, psychosis, cognitive behavior, and abuse by the young and old is very disturbing, but expected. We need to keep educating everyone regarding drug and alcohol abuse and promote responsible use of marijuana, both medicinally and recreationally.
Robert G. Bell, Ph.D., is president and owner of Drug and Biotechnology Development LLC, a consultancy to the pharmaceutical industry and academia for biological, drug, and device development.