Marijuana Is Not the Solution for PTSD

Business — Evidence shows it does not treat PTSD in the long-term, and may worsen symptoms

by
Libby Stuyt, MD



April 10, 2023

A growing number of states have identified post-traumatic stress disorder (PTSD) as an approved condition for medical marijuana. According to Colorado’s Medical Marijuana Registry, there are 70,533 patients as of February 2023 with an active medical marijuana registration in the state, and 10,734 of them indicate PTSD as the reason they are using medical marijuana. This is despite the lack of any high-quality, randomized, controlled studies proving that marijuana helps PTSD in the long-term. Because of this lack of evidence, the American Psychiatric Association adopted a policy in 2019 opposed to using medical cannabis treatment for PTSD.

While many people find that cannabis seems to initially help PTSD symptoms, it likely does this by providing some temporary relief, numbing the individual and disconnecting them from the traumatic emotions. However, to keep the symptoms at bay, the individual often needs to use daily, sometimes multiple times a day, which can then set them up for significant consequences associated with daily cannabis use, such as cannabis use disorder (CUD), psychotic symptoms, cognitive problems, suicidal ideation, worsening depression and anxiety, and cannabinoid hyperemesis syndrome.

Outcomes of Marijuana Use for PTSD: A Review of the Literature

The problems with regular cannabis use in those with PTSD were demonstrated by a 2020 study from Canada in which anonymous data was obtained from a phone app, Strainprint. In the study, 404 medical cannabis users, self-identified as having PTSD, used the app to track symptoms of intrusive thoughts, flashbacks, irritability, and anxiety. The users would then indicate the strain of cannabis they were about to use and the effects on their symptoms. The results indicated that acute cannabis intoxication provided temporary relief from intrusions, flashbacks, irritability, and anxiety. However, baseline PTSD symptom ratings did not change over time, and the researchers detected evidence that people used higher doses over time to manage anxiety, indicating the development of tolerance to the drug. They concluded that while these results indicate that cannabis may reduce PTSD symptoms in the short-term, it may not be an effective long-term remedy for the disorder.

There have been an increasing number of studies demonstrating that the use of marijuana can worsen PTSD over time. An observational study assessed 2,276 veterans treated in VA PTSD treatment programs at the time of intake and then again 4 months after discharge. They found that those who had been using marijuana prior to the program but stopped had the lowest level of PTSD symptoms 4 months post-discharge, and second lowest were those who never used marijuana. Those who started using marijuana again after the treatment program had the highest levels of violent behavior, alcohol use, and PTSD symptoms.

A more recent study using the 2019-2020 National Health and Resilience in Veterans Study (NHRVS) data on 4,069 U.S. military veterans from around the country found that frequent cannabis use worsens PTSD symptoms in veterans. Those who used cannabis frequently were roughly twice as likely to screen positive for co-occurring major depressive disorder, generalized anxiety disorder, and suicidal ideation. They also showed small-to-moderate decrements in cognitive functioning.

A prospective study of 361 veterans returning from deployment in Iraq and Afghanistan found more frequent cannabis use linked to greater severity in PTSD-related intrusion symptoms 6 months later and a prospective association from PTSD diagnosis to cannabis use disorder (CUD) diagnosis 1 year later. Importantly, there was no evidence of improvement in PTSD-related intrusion symptoms or remission in PTSD diagnosis in association with long-term use of cannabis. The researchers concluded that these results strengthen the argument for a causal link between frequent cannabis use and subsequent greater severity of PTSD-related intrusion symptoms and the links between PTSD and CUD.

This is especially concerning considering the evidence that CUD is associated with suicidal ideation and suicide attempts in veterans. Another study found that while neither past 30-day heavy alcohol use nor opioid use predicted an increase in suicidal ideation or suicidal behavior, increased marijuana use, in the presence of elevated PTSD symptoms, strongly predicted suicidal ideation, PTSD symptoms, and suicidal behavior in veterans.

An overview of peer-reviewed studies and randomized controlled trials in humans of THC or THC and CBD in PTSD from 1974 to 2020 reported that low doses of THC (7.5 mg THC) can potentiate fear memory extinction in healthy volunteers and reduce anxiety responses in anxious and PTSD patients without inducing a psychotic effect. However, high doses of THC (greater than or equal to 10% THC), do not facilitate fear memory extinction and are related to clinically relevant anxiogenic and psychotic effects in healthy volunteers. The fact that most products available in medical and recreational marijuana dispensaries are greater than 15% THC (with many in the 60-90% THC range) complicate attempts from patients to find products that help with PTSD.

Evidence-Based Treatment Exists

As an addiction psychiatrist and a medical director of a 90-day inpatient treatment program, I have overseen the treatment of hundreds of people with PTSD. I know it is a very treatable condition. Evidence-based treatments have been shown to help permanently alleviate symptoms, allowing patients to process and assimilate their memories so they no longer bother the person when they are recalled. A recent meta-analysis of randomized controlled trials of evidenced-based therapies found that narrative exposure therapy (NET), cognitive processing therapy (CPT), and eye movement desensitization reprocessing (EMDR), had the highest correlation with overcoming the PTSD diagnosis.

I’ve seen that when a patient is actively using an addictive substance such as cannabis while attempting to engage in these therapies, the treatment is less effective. Another concern with cannabis use by someone in PTSD treatment is that cannabis users show increased susceptibility to false memories. It is extremely difficult to treat fixed delusions or false memories that never actually happened.

The evidence shows that marijuana does not treat PTSD in the long-term, and contributes to worsening symptoms and outcomes. Meanwhile, we have very effective, evidence-based treatments available for PTSD, which can eliminate the symptoms and the diagnosis. They are more effective when the patient quits using cannabis. It is imperative that treatment providers educate their patients with PTSD and follow the science when recommending treatment options.

Libby Stuyt, MD, is an addiction psychiatrist in Colorado, and a board member of the International Academy on the Science and Impact of Cannabis. The opinions of the author are her own and do not necessarily reflect those of any organization with which she is affiliated.