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Up In Smoke?

Most Studies Fail to Confirm Medical Marijuana Claims

Since 2007, the National Institutes of Health has awarded more than $14 million for research of components of cannabis and whether they could be used to treat diseases or conditions. This research funding is a small part of the thousands of studies of Marijuana. If Medical Marijuana (as opposed to FDA reviewed marijuana-based medicine) is the helpful wonder drug that advocates claim, research should confirm its benefits. Does research support the claims often seen on the Internet?

2017 Comprehensive Review

A study by a panel of 16 scientists with the National Academies of Sciences, Engineering and Medicine recently looked at over 10,000 studies of marijuana conducted since 1999. They compiled and studied more than 100 claims about the health effects of marijuana, including helpful and harmful effects.

In January, their report stated that there really is not enough evidence to conclude that smoking or eating marijuana can effectively treat most of the symptoms and diseases it is advertised as helping.

The review did find evidence that cannabis can alleviate some nausea and vomiting associated with cancer treatment and spasms and pain associated with Multiple Sclerosis, things already known.

The panel also reaffirmed that research does conclusively confirm the following risks:

- Mental Health: Cannabis use is likely to increase the risk of developing schizophrenia, social anxiety disorders and, to a lesser extent, depression. Heavy marijuana users are more likely to report suicidal thoughts than non-users.

- Injury: Evidence affirms that driving while high increases the risk of a car accident.

- Youth Dangers: In states where marijuana has been legalized, evidence suggests that children are at more risk of ingesting marijuana. Cannabis use could also harm adolescents’ educational and social development.

Large Study of Veterans

An August 14, 2017 article in the UK Daily Mail opens with this sentence: "There is no conclusive evidence that marijuana helps with chronic pain and post traumatic stress disorder, experts say." The article discusses a 20-year study from the US Department of Veterans Affairs involving 47,000 military veterans from 1992 - 2011. From this group of veterans the researchers could not conclusively say that medical marijuana has benefits when dealing with people with PTSD. It also noted that one study of veterans with PTSD showed a "significant" worsening of symptoms among many of those who started or continued using cannabis during the study.

As for chronic pain, the results in one clinical trial recorded only 28% of participants feeling a change when using nabiximols - a mixture THC and CBD. However, there were 16% of participants who also felt a change when taking a placebo. This suggests psychological effects are possible when someone thinks they are taking a medicine.

Questionable Help for Chronic Pain

Two articles published this fall in the journal Annals of American Medicine find little evidence for the relief of chronic pain. The researchers analyzed 27 studies that examined the use of cannabis products for chronic pain in adults. They found insufficient evidence to draw conclusions about whether medical marijuana was helpful to pain with one exception: neuropathic or nerve pain. Yet, even there, the team found only weak evidence that cannabis alleviates chronic neuropathic pain.

Medical Marijuana & Dementia

A Dutch study published in the journal Neurology recently concluded that cannabis pills containing tetrahydrocannabinol (THC) did not aid in curbing symptoms such as aggression, pacing, and wandering in dementia patients. Dr. Geke A.H. van den Elsen of Radboud University Medical Center in Nijmegen, the Netherlands, said, “Ours is the largest study carried out so far on evaluating this drug for behavioral symptoms of dementia.”

Poor Research Supporting Cannabis

Yale University School of Medicine recently looked at 79 randomized clinical trials involving 6,462 participants that assessed the effectiveness of cannabinoids in treating the symptoms of an array of medical conditions. While the majority of studies claimed that cannabinoids could treat symptoms of certain medical conditions, the researchers found many of these studies were not statistically significant. They concluded that approval of medical marijuana in many states is premature and has been based on poor quality studies, patient testimonials or other non-scientific evidence.

Harvard: No Such Thing as Medical Marijuana

In 2015, Dr. Bertha Madras, the chair of the Division of Neurochemistry at Harvard Medical School explained, “In reality, there is no such thing as “medical marijuana”; that is, there is not a particular type of marijuana used for medicinal purposes, let alone for a specific, proven medical purpose. Physician recom mendations for medicinal use of smoked marijuana are not grounded in systematic, evidence-based research, which is the hallmark of our system.”

Researching Colorado Youth

In September 2015, the Federal Government released a 166-page report on the impact of marijuana decriminalization in Colorado, including the use of medical marijuana. One of the report's key findings was that the number of children aged zero to five exposed to marijuana increased 268% from 2010 to 2013: triple the national average.

The report showed that more young people aged 12 to 17 were using marijuana as well. When asked during a national survey in 2012 whether they had used marijuana in the past month, 10.47% of Colorado’s youth said they had: 39% higher than the national average.

The report also found that drug-related school suspensions and expulsions increased 32% in 2012- 2013 school years. The majority of expulsions were for marijuana violations. ( A 2012 paper in the Journal of Adolescent Health found that youth who smoke marijuana were more than twice as likely to abuse prescription medicines than those who don't.)

In August 2012, researchers at the University of Colorado School of Medicine found that three-quarters of teens in two Denver substance abuse programs admitted to having used medical marijuana bought or grown for someone else. Their median use of medical marijuana was 50 times. Only one of the 112 teens in the study using medical marijuana was an approved patient.

A 2017 report Legal Marijuana and Youth: New Evidence by David Murray of the Hudson Institute concludes, "Medical-marijuana laws amplify rates of youth marijuana use, arguably because they allay social stigma and placate fear of a negative health outcome."

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