A New Study Says There’s No RCT Evidence Cannabis Treats PTSD. Tell That to the 900,000 Patients in Florida.

A landmark study published this month in The Lancet Psychiatry is about to become the most-cited document in a hundred conservative statehouses. The paper — a systematic review of 54 randomized controlled trials spanning 45 years and nearly 2,500 participants — found no significant evidence that cannabis is effective in treating PTSD, anxiety, depression, or several other mental health conditions for which it is commonly recommended.

Kevin Sabet, CEO of Smart Approaches to Marijuana and one of the most effective anti-cannabis advocates in America, wasted no time. In a STAT News op-ed published today, he calls the findings a confirmation of what he’s argued for years: medical marijuana programs were “primarily a political move, decided at various ballot boxes,” and the evidence was never there.

He might be right about the evidence. He is profoundly wrong about what to do with it.

In Florida alone, the state’s Office of Medical Marijuana Use currently tracks over 900,000 active registered patients. A substantial portion hold their cards for PTSD and anxiety — conditions now squarely in the crosshairs of this study’s findings. In Texas, where the Compassionate Use Program has been tightly controlled and slowly expanded, PTSD was added as a qualifying condition in 2021 after years of lobbying by veterans’ groups. Virginia, which has one of the fastest-growing medical programs in the South, includes both PTSD and anxiety disorders. North Carolina, Georgia, the Tennessee ban, and Kentucky — states with no adult-use market and medical programs ranging from narrow to nonexistent — now have a research citation that will almost certainly show up in their next session’s committee hearings.

This is the moment Southern legislators have been waiting for. And they’re not going to miss it.

Let me be precise about what the study actually found, because it matters.

The University of Sydney-led research team reviewed every randomized controlled trial (RCT) testing cannabinoids as the primary treatment for mental health disorders. Their conclusion: “There were no significant effects on outcomes associated with anxiety, anorexia nervosa, psychotic disorders, post-traumatic stress disorder, and opioid use disorder.” The only condition where cannabis showed statistically significant benefit was cannabis use disorder itself — specifically, CBD reduced cannabis craving.

That’s a narrow finding for a sweeping headline. And the researchers’ own caveats are important: the number of trials was small, the study populations were limited, and the research field is plagued by methodological inconsistency. “We found no high-certainty evidence,” they wrote — not “we found evidence it doesn’t work.”

That distinction is everything, and it’s the one Sabet’s op-ed glosses over.

Here is the problem that no federal committee hearing or legislative floor speech ever seems to confront honestly: the same legal framework that anti-legalization advocates cite to justify caution about cannabis is the reason the RCT evidence base is so thin.

Cannabis is a Schedule I controlled substance under federal law. That classification — which asserts no accepted medical use and a high potential for abuse — makes clinical research extraordinarily difficult, expensive, and slow. DEA licensing requirements, supply limitations from the NIDA monopoly, and restrictions on patient populations have consistently hampered the kind of large, longitudinal RCTs that would produce high-certainty evidence.

The system is designed to produce exactly this result: no research, therefore no evidence, therefore no legalization, therefore no research.

For Southern patients, this is not an abstract irony. It is the reality of their medical care. A veteran in North Carolina using cannabis for combat-related PTSD is not doing so because a randomized trial told him to. He’s doing it because conventional treatments — SSRIs, antipsychotics, years of VA appointments — did not work, and this did. He is doing it because 91.5% of PTSD patients in a nationwide NORML patient survey reported that cannabis relieved their symptoms. That’s not RCT evidence. It is also not nothing.

The political weaponization of this study in the South will not be subtle. Florida conservatives who voted against the legalization amendment last November now have new ammunition. the Texas smokeable hemp ban legislators who have spent years trying to limit the Compassionate Use Program will quote The Lancet. Opponents of any medical expansion in Georgia and North Carolina have a peer-reviewed paper to wave on the House floor.

None of them will mention the Schedule I research catch-22. None of them will mention that the absence of RCT evidence is not the same as evidence of absence. None of them will acknowledge that their own obstruction of research is part of why the evidentiary record looks the way it does.

Sabet writes that the increasing normalization of marijuana use “has been a public health disaster.” The data on cannabis-related hospitalizations, cannabis-involved traffic fatalities, and teen use rates in legal states does not support that characterization. But it doesn’t need to, because the op-ed isn’t really about public health. It’s about political timing.

The study landed on April 1. Florida’s 2026 legislative session is underway. Texas’s the full legislative tracker convenes in January. Advocacy groups have been watching these numbers.

What should actually happen is this: the Lancet findings should accelerate research funding, not patient restrictions. The honest response to an evidence gap is to fill it — remove Schedule I barriers, fund clinical trials, and let scientists study cannabis the way they study every other medicine in America.

The dishonest response is to use the absence of research as justification for preventing the research.

For the hundreds of thousands of Southern patients who have built their daily pain management, their sleep, their ability to work and parent and function around access to medical cannabis, the difference between those two responses is not academic. It is their lives.

They didn’t get their medical cards because a clinical trial told them to. They got them because their doctors, working within a legal framework their states created, decided they qualified. That framework is now under pressure from a study that its own authors acknowledge is constrained by the very regulatory barriers that reformers have been trying to dismantle for twenty years.

The South’s anti-cannabis politicians will call this a vindication.

It is actually an indictment of the system they’ve spent decades defending.

Leila Castillo covers cannabis policy and culture across the American South for CannabisInquirer.com. She is based in Miami.