Cannabis and PTSD: The Research Just Isn’t There

The Scientific Answer Is Maybe.

PTSD Source: Wikileaf

It is becoming more common to see post-traumatic stress disorder make the list of qualifying debilitating medical conditions a patient must have to be eligible for a state’s medical marijuana program.

Theoretically, this makes good sense. The two most abundant cannabinoids housed in the plant are cannabidiol and tetrahydrocannabinol, both of which interact with the endocannabinoid system in ways that, for the most part, are beneficial. In fact, cannabis has been identified as a stress and anxiety reducer and a sleep aid, each of which targets a debilitating PTSD symptom.

It turns out that a lot of the hype behind cannabis as treatment for PTSD is still mainly theory—there is a lot of anecdotal and observational evidence suggesting the potential. But those forms of evidence can do no more than offer a resounding “maybe.”

All Researchers Know is That They Don’t Know

The research exploring cannabis’ relationship with PTSD is conclusive of two things: there isn’t enough research and the findings are ambivalent. A review of the literature published in The Mental Health Clinician in March 2018 evaluated existing evidence on the therapeutic use of cannabis for PTSD. While most of the findings suggest that cannabis has potential as a treatment, a significant portion claims that cannabis is not only an ineffective treatment, it has the potential to make symptoms worse.    

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Researchers scanned Ovid MEDLINE and Google Scholar—the two most relevant sources for obtaining peer-reviewed research—and only found 5 studies investigating cannabis as a treatment for PTSD. To put that in perspective, a MEDLINE search of “cannabis cancer” will yield 699 results—and the consensus is that there is a paucity of research in this area as well.

Of the 5 studies that were identified by the review, only one actively used cannabis as a PTSD treatment. 3 of the studies did not actively use cannabis as a treatment but evaluated their patients’ emotional health after using cannabis on their own. The remaining study collected retroactive data by asking PTSD patients to recall how they felt when they were using cannabis versus when they were not.

The Studies Have A Lot Of Problems

The one study that actively used cannabis only tested the treatment on 10 patients for the short duration of 3 weeks. No placebo was used, so there was no baseline comparison tool. Moreover, the patients were not monitored for simultaneous drug use, and one patient admitted to using marijuana close to the start of the study (a factor that suggests the possibility that the patient may have continued to use marijuana in addition to receiving the doses given for treatment). The results of the study showed that cannabis use resulted in an overall improvement in PTSD symptoms. 

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Of the 3 studies that checked patient emotional response after cannabis use, one was part of a larger study including patients that were actively combating substance abuse disorders, including alcohol and cocaine use. Because the cannabis was not administered by the researchers, there was no analysis of dosage, potency, or another variability. Another of these studies used a pool of eighty patients who were not necessarily diagnosed with PTSD, but with a cluster of symptoms, and who were also applying to New Mexico’s medical marijuana program—that last factor made them extremely biased to confirm positive outcomes when reporting their use of marijuana and how it affected their symptoms. These two studies both found that cannabis use was associated with decreased PTSD symptoms. 

The third study in this group included treatment to prevent PTSD patients from relapsing into cannabis use—so there was a negative association to cannabis use prior to the patients being tested. Additionally, this study was examining the effects of cannabis use disorder, not the effects of a carefully dosed therapeutic program. It should come as no surprise that this study concluded that cannabis use disorder intensified the symptoms of PTSD.   

Vector of a human brain made of marijuana leaves

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The final study evaluated long term use of cannabis on PTSD symptoms but relied on self-reporting patients to collect the data. Patients were separated into 4 categories: never users, stoppers, continuing users, and starters. The study found that starting cannabis use after receiving a PTSD diagnosis exacerbated symptoms while stopping reduced symptoms, and that long-term cannabis use was associated with greater severity of violent behavior.

What Conclusions Can Patients Make?

The short answer is this: none. Although current literature suggests that cannabis has the potential to treat PTSD symptoms, none of the studies conducted have been randomized, controlled, clinical trials evaluating active cannabis use.

Moreover, there are only 5 studies specifically dealing with PTSD and cannabis. In the world of cannabis research, that’s next to nothing. That means that treating PTSD with cannabis comes with a lot of risks.

The review recognized that cannabis’ function as a CB-1 receptor agonist has the potential to result in “significant subjective improvement in nightmare intensity, sleep time, quality of sleep, and daytime flashbacks.” However, the reviewers also cautioned against recommending cannabis under current legislative and medical realities for these reasons:

  • The risk of developing cannabis abuse disorder is high in such a vulnerable population where addiction is already a common risk factor. 
  • Because regulation of cannabis is neither universal or federally legal, it is very difficult to oversee the quality and dosing of cannabis as well as understand the potential side effects including cardiovascular adverse responses the scientific community is still trying to understand.
  • A lack of medical insurance coverage may make cannabis financially unfeasible for some patients.
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The safest play is to opt for cannabis products and strains that are low in THC and very high in CBD. The adverse psychological effects of cannabis are caused by THC, and because CBD produces no psychoactive effects at all, it’s unlikely that feelings of paranoia or anxiety will be exacerbated by CBD rich cannabis. Cannabis strains like Charlotte’s Web, ACDC, Harlequin, and Cannatonic are famous for their high CBD and low THC percentages.

If you have conventional therapy-resistant PTSD (and odds are you do if you are a veteran), these risks may be worth the potential relief cannabis has anecdotally provided. In the most extreme cases, doing nothing to alleviate the symptoms can be just as risky as trying a novel therapy. In either case, proceed with extreme caution, and vote for candidates who will fight to lift cannabis prohibition. The federal cannabis ban remains the largest obstacle to obtaining the research necessary to understand how this elusive plant works.

Cannabis and PTSD: The Research Just Isn’t There was last modified: by
Dianna Benjamin
About Dianna Benjamin
Dianna Benjamin is a freelance writer, teacher, wife, and mom horrified and fascinated by social justice and our inability--yet constant pursuit--to get it right.