In what was widely viewed as a blow to expanding marijuana research for such conditions as post-traumatic stress disorder (PTSD), the U.S. Drug Enforcement Administration (DEA) recently rejected a petition to reclassify cannabis from its current status as a Schedule I drug.

Cannabis remains in the DEA’s most restrictive category along with heroin and LSD, despite the arguments of researchers that it is a safe and effective treatment for PTSD, and various forms of pain relief and oncology therapy.

“Using established scientific standards that are consistent with that same FDA drug approval process and based on the FDA’s scientific and medical evaluation, as well as the legal standards in the CSA, marijuana will remain a Schedule I controlled substance,” the DEA announced in a letter to the petitioners.1 “It does not have a currently accepted medical use in treatment in the United States, there is a lack of accepted safety for its use under medical supervision, and it has a high potential for abuse. If the scientific understanding about marijuana changes — and it could change — then the decision could change.”

The DEA has five drug categories, with the remainder going from Schedule II (i.e., cocaine, oxycodone) down to Schedule V (cough preparations and analgesics). Though there has been a lot of research with medical marijuana, advocates of rescheduling the drug say the current classification hinders establishing large clinical trials that could demonstrate efficacy and remove the “no accepted medical use” label. The result is a classic catch-22, as research advocates note that “the federal government has made it virtually impossible for researchers to study the therapeutic efficacy of cannabis.”2

One of the petitioners who requested the DEA reclassify cannabis said he will appeal the decision.

“I had expected potentially that they would move it to Schedule II, but even that is not considered appropriate placement,” says Bryan A. Krumm, MSN, RN, CNP, BC, a psychiatric nurse practitioner at Sage Neuroscience Center in Albuquerque, NM. “Keeping it in Schedule I only strengthens my argument with the Court of Appeals that this administrative process is futile. I argue that it is the states, not the federal government, that should make the determination of what is accepted medical use. [The DEA] is overstepping their bounds in making this determination when 25 states have accepted medical use of cannabis.”

Krumm recently published a paper3 citing a “broad range of therapeutic effects seen in treating PTSD with cannabis,” while underscoring the alarming number of suicides in veterans with the condition. Given its effect on the “underlying neurobiological processes that are involved in PTSD, cannabis is so much more effective than pharmaceuticals for treating PTSD,” he tells IRB Advisor.

Despite its refusal to reclassify the drug, the DEA letter states that it will continue to support marijuana research. “For instance, DEA has never denied an application from a researcher to use lawfully produced marijuana in a study determined by the Department of Health and Human Services (HHS) to be scientifically meritorious,” the agency stated.


  1. Rosenberg C. Drug Enforcement Administration. Letter from the office of the administrator. Aug 11, 2016:
  2. Clinical Trials.
  3. Krumm, BA. Cannabis for posttraumatic stress disorder: A neurobiological approach to treatment. Nurse Practitioner 2016; 41:50–54.