Op-Ed: Can pot blunt the opioid epidemic? We don’t know because the federal government blocks research.

An epidemic of opioid abuse is ravaging the United States and, as we look for ways to respond to it, some see cannabis as part of the solution, while others see it as part of the problem. This is just one area in which unbiased scientific research is necessary, but outdated federal legislation, having concluded almost 50 years ago that there is no medical value to cannabis, is blocking all meaningful efforts to understand the real benefits and risks of the plant.

There are critical open questions about cannabis, and without research conducted under rigorous scientific standards, we will not find answers. If you think these questions don’t really matter in daily life, let’s look at three scenarios.

Your friend is one of the 1,125,000 people in California who use medical cannabis. Before going to bed, he drinks a cannabis tea because it helps him go to sleep. The morning after, he feels well rested and doesn’t experience any aftereffects. But one day, as he is driving to work, the police stop him for a random blood THC test (this type of test is already in use in Colorado and may be adopted in California). Your friend turns out to be THC positive and loses his driver’s license, even though there is no correlation between blood THC levels and intoxication. The same person can have detectable blood THC levels and be perfectly functional, or have undetectable levels and be impaired. We need research to develop objective, unbiased ways of measuring cannabis intoxication, or innocent people will end up paying for a crime they did not commit.

Or let’s say your grandfather is convinced that cannabis is the only thing that helps him with his arthritis pain. He is not alone in believing this — cannabis use in persons over 50 has tripled in the last 10 years, a phenomenon primarily driven by self-medication for pain and sleep problems. You are happy for grandpa, but then you notice that he has become more forgetful than he used to be. Is this a normal consequence of age, or a side effect of the drug? Will forgetfulness turn into memory impairment? We can’t answer this question now, because the effects of cannabis have never been studied in elderly people. Research shows that that in old mice, low doses of cannabis may actually improve memory — but what about in humans?

One last example, which takes us back to the opioid crisis. States in which cannabis is legal have 25% fewer deaths for opioid overdose than states in which medical use of the drug is not allowed. These are credible data, but do not necessarily mean that cannabis is a solution to the opioid crisis. Cannabis reduces many forms of chronic pain in people, but we do not know if it can replace opioids. Nor do we know if the use of cannabis attenuates or worsens the risk of developing an opioid addiction.

Finding the answers to all of the above questions is more than feasible.

Yet the Controlled Substance Act of 1970, or CSA, stands in the way. First, researchers seeking to study cannabis and its chemical constituents (even the innocuous cannabidiol) may only use plant material from a single federal contractor, the University of Mississippi. That cannabis is very different from the cannabis generally available to the public in California and elsewhere, which creates a problem of “external validity�: what researchers are allowed to study in the lab or the clinic does not tell them much about what happens in the real world. In addition, the Food and Drug Administration and the Drug Enforcement Administration must approve any use of the University of Mississippi cannabis, a process that requires researchers to jump through unnecessary hoops.

This is not news. We have known for years that the Controlled Substance Act is the single greatest impediment to increasing our knowledge of cannabis. It matters now because, come January, Proposition 64 (the Adult Use of Marijuana Act approved by California voters in November 2016) will take effect in full and cannabis will be legally available for recreational use in the most populous state in the union.

California’s Bureau of Cannabis Control is working hard to put sensible guidelines in place and regulate its use, but even the most thoughtful regulation cannot replace research. If science does not fill the knowledge void, then interest-driven pseudo-science will. Ideologists and special interests are already pushing hard in that direction.

Proposition 64 calls for and funds research on cannabis. Despite out-of-date federal legislation, it is essential that we implement this key component of the proposition and support the rigorous scientific work needed by medical providers, consumers, law enforcement and entrepreneurs alike.

Daniele Piomelli and Bob Solomon are directors of the UCI Center for the Study of Cannabis.

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