Legalizing marijuana will increase our opiate epidemic
By Heidi Heilman | March 3, 2016, 14:23 EST
We have, for some time, known that the more marijuana there is in our communities, the more opiate and heroin use rises. Now, brain science is beginning to explain why.
Studies reveal that the cannabinoid-opioid systems of the brain are intimately connected. There is a functional interaction between the mu and Cb1 receptors of the brain and these receptors commonly exist together on brain cells. In the areas of the brain where cannabinoids bind, opioids bind as well. If you modify one system, you automatically change the other.
The mechanism is not yet well understood. With marijuana research, we are where we were in the 1920s and 30s with tobacco research linking smoking to cancer. More research is needed. But, ultimately, cannabinoids and opioids are known to strictly interact in many physiological and pathological functions, including addiction. Overall, evidence confirms a neurobiological convergence of the cannabinoid and opioid systems that is manifest at both receptor and behavioral levels.
What does this mean? We are learning that brain cross-talk between the endocannabinoid and endogenousopioid systems may cause, if there has been early brain exposure to marijuana, changes in the sensitivity to other drugs of abuse such as heroin. Specifically, sensitivity to drugs may be blunted, which would cause a greater risk for abuse and addiction.
This new science suggests that a person who uses marijuana as a teenager may be increasing his/her risk of opiate addiction later in life. For example, a 20-year-old who takes an opiate pain killer for a skiing injury or wisdom tooth removal may be much more at risk of becoming addicted to that pain killer as a result of his or her earlier marijuana use — no matter how insignificant that earlier use may seem.
This does not mean, of course, that every teen marijuana user will be challenged with opioid addiction when they take an opiate-based pain killer later in life. Nor does this remove the enormous responsibility that opioid medications bear in the current opiate crisis. But it does put some teeth behind that old-school term “gateway drug,” as now there is clear scientific evidence of a neuropathway link between cannabinoids and opioids in the brain.
Evidence suggests that the opioid-marijuana brain cross talk is real and the newest research shows very important experimental evidence on “epigenetics.” A study of rodents conducted at the Hurd Laboratory at the Mount Sinai School of Medicine showed that rodents exposed to THC in their adolescent years had offspring that were primed for addiction.
The rodents did not even need to be using THC during childbearing timeframes. For example, if an adolescent rodent used THC, then stopped during adulthood, and then later conceived and gave birth, offspring still showed epigenetic evidence of brain structural changes that primed them for addiction. The research has yet to be reproduced in humans, but other studies on trans-generational effects of other drugs in humans appear consistent with these discoveries in rodents.
The science suggests, therefore, that legalizing marijuana will not only expose more people to a serious decline in cognitive & mental-health functioning (as revealed from the volumes of marijuana studies showing harmful outcomes of memory loss, depression, paranoia, psychosis, schizophrenia and addiction), but possibly also prime certain segments of the population — including unborn children — for more opiate addiction and brain changes.
This possibility — that marijuana exposures in the brain are a foundational feature of the opiate addiction crisis — deserves to be weighed heavily in the current decision-making process. I hope we learn more about this opioid-cannabinoid brain connection, and very soon.
Those in the field of substance abuse and drug use prevention are grateful to our esteemed researchers in Massachusetts and throughout our nation who are working diligently every day, not only to figure out this opioid-cannabinoid neuropathway link, but to explain it to the rest of us so we can begin to truly understand what is at stake. This science is worth considering as the marijuana lobby pushes for full government protection to engineer, produce, market and sell marijuana products in the same manner as tobacco.
Heidi Heilman is the CEO of Edventi and President of the Massachusetts Prevention Alliance, a non-profit organization serving to protect the health and well-being of youth through sound drug and alcohol policies.