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Why is it easier to study heroin than marijuana?

Many can buy pot in any form or potency, but federal regulations make any research into the drug nearly impossible

January 9, 2015 4:00PM ET Updated January 16, 2015 6:22PM ET

by Jacob Ward @_jacobward_

Tune into our "Year on Pot" special: Friday, Feb. 6 at 10 p.m. ET

An enormous number of people are using marijuana. Nearly 20 million people say they've used it in the prior month, according to the 2012 National Survey on Drug Use and Health, making it America's favorite illicit drug. In California, where medical marijuana has been legal since 1996, half a million people have prescriptions. The nonprofit ProCon.org estimated that if every state legalized medical marijuana, there would be almost 2.5 million regular medical users alone.

Yet, when state policymakers write new marijuana laws and medical clinics dole out marijuana prescriptions, the risks and benefits touted are largely anecdotal. Compared to other pharmaceuticals, and even other illegal drugs, studying marijuana in any formal sense is nearly impossible under federal regulations.

Although state laws have decriminalized marijuana or, in the case of Colorado, Washington state, Alaska, Oregon, and Washington, D.C., even legalized it, federal law continues to classify it as a Schedule 1 drug. It's a label the government reserves for drugs with no accepted medical use in the United States, and which carry a high risk of abuse. Over the years, the Drug Enforcement Administration has repeatedly rejected petitions to reclassify marijuana, asserting, "no sound scientific studies support medical use of marijuana for treatment" and that "the clear weight of the evidence is that smoked marijuana is harmful." So, marijuana remains in Schedule 1, along with ecstasy, heroin, and LSD.

There isn’t a day that goes by that I don’t see a patient that has nausea, loss of appetite, pain, depression, insomnia, and I could recommend one medicine to treat all five of those instead of writing a prescription for five different medicines.

Dr. Donald Abrams

cancer and integrative medicine specialist

But unlike those drugs, or any other illegal drug, marijuana research is also subject to an open-ended public health review by the Public Health Service. This review is unique to marijuana. It’s easier to study the potential medical benefits and risks of heroin, which has seen the number of overdose deaths increase by 50 percent in just two years, than it is to study the same aspects of marijuana. And while other forms of permission for drug research have a built-in deadline of weeks or months, the public health review has no timetable.

Brad Burge, the spokesman for MAPS, said it's taken more than decade for their marijuana study to get the necessary federal approvals.

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“In our case it took us 12 years to get approval from the Department of Health and Human Services,” said Brad Burge, director of communications for the Multidisciplinary Association for Psychedelic Studies, which privately funds studies of marijuana and other drugs, and sought to study the potential therapeutic benefits of smoked marijuana.

"There were six month delays in emails,” Burge added. "There was in fact an internal recommendation that Health and Human Services grant permission that the executive of Health and Human Services decided not to follow."

Then, last year, the organization finally received its approval — making it one of only four organizations since 1999 to receive federal permission to study the potential benefits of smoking marijuana — for a study of the effects of marijuana on PTSD-afflicted veterans. Now, Burge said the problem is receiving the marijuana itself.

Only the National Institute on Drug Abuse, or NIDA, which maintains a small grow operation at the University of Mississippi, is allowed to supply marijuana for federally approved studies. At a time when marijuana is available in almost any form and any potency to private buyers in Colorado and Washington, there’s no telling when MAPS could receive its supply from NIDA.

“We have approval to purchase it from NIDA,” Burge said, "but they won't give us a time estimate on when they'll be able to deliver it.”

According to Burge, a similar study of MDMA, the active ingredient in ecstasy, ran into no such problems. MAPS was able to arrange to have the drug synthesized by any number of federally approved suppliers in California, and the organization now has more of the drug in its vault than researchers can possibly use.

Dr. Donald Abrams believes cannabis can ease pain, but that it isn't a cure. "Most of the patients that I've cared for have used it, probably smoked it," he said. "If cannabis cured cancer, I'd have a lot more survivors."

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NIDA is also less inclined to support studies that are looking at possible benefits of marijuana use, according to Dr. Donald Abrams, a cancer and integrative medicine specialist at the University of California, San Francisco.

“Generally, they will only fund your study if you're looking at cannabis as a substance of abuse or something that's harmful,” he said.

Abrams is one of the few physicians to ever receive federal permission to study marijuana and he did so by studying abuse potential and medical risks, or by receiving limited funding from state sources. In his work, he found, as have the few researchers who have looked at the issue, that the cannabinoids in marijuana can ease inflammation and pain.

“There isn’t a day that goes by that I don’t see a patient that has nausea, loss of appetite, pain, depression, insomnia, and I could recommend one medicine to treat all five of those instead of writing a prescription for five different medicines,” said Abrams. "I’ve seen it for the past 32 years, time and time again."

Abrams believes marijuana can improve the therapeutic effects of other pain medications and allow for lower doses of addictive opiate drugs, like Vicodin, Oxycontin and Percocet, which are tied to 16,000 overdose deaths in the U.S. each year.

In his experience, Abrams said marijuana seems to improve the painkilling qualities of opiate drugs, possibly reducing the patient’s risk of pill overdose.

"I called the DEA and I said, 'How about cannabis?' And they said we would never be able to fund a clinical trial looking at a Schedule 1 substance as an adjunct to opiates,” Abrams said, and then shrugged. "Science has been impeded by the politics."

Marijuana research regularly splashes front pages. But those studies often involve small sample sizes and the results aren't repeated, such as a 2012 Duke study that purported to find a link between heavy marijuana use and IQ decline among teenagers. At the same time, small studies and anecdotal stories suggest marijuana, or its components, could treat diverse conditions, including cancer, Crohn's Disease, epilepsy, HIV and Alzheimer's disease. But funding, legal issues and stigma make it uniquely difficult to set up the necessary clinical trials.

Meanwhile, at least five states, including California, which accounts for 12 percent of the U.S. population, appear poised to vote on ballot measures in 2016 that would legalize the drug, only widening the gap between the number of people who use marijuana and a true scientific understanding of its effects on the body.

Correction: January 16, 2015

An earlier version of this article stated that MAPS' study about the effects of marijuana on PTSD-afflicted veterans is the first time an organization has received federal permission to study the potential benefits of smoking marijuana. Since 1999, the federal government has cleared three other organizations for research grade marijuana to study its possible therapeutic effects: San Mateo County Health Department, Health Canada and the University of California at San Diego. The MAPS study is the first to receive permission to provide federal marijuana to PTSD-afflicted veterans.