Research Update: Marijuana for PTSD
If you’ve heard any of my talks about medical marijuana, you’ll know that one of my biggest frustrations with the medical marijuana system is the inclusion of PTSD as a qualifying condition. As a psychologist, particularly one who trained for 3 years in the VA Hospital system, its inclusion is baffling and disappointing: if you talk to anyone who actually treats PTSD in a professional context, they will tell you that marijuana and other addictive substances are contraindicated for PTSD.
Driving home this point, three studies were published very recently:
This study (2021), which found that any benefits marijuana has on PTSD are explained away by the placebo effect in a randomized-controlled trial.
This study (2021), which found that marijuana use in a Veteran population is associated with other substance use, negative health outcomes, psychiatric disorders, self harm, and suicidality.
This longitudinal study (2020), that found an association between marijuana use and worsening PTSD symptoms after 6 months in a Veteran population.
Despite this sort of evidence, not to mention clear anecdotal consensus amongst professionals, you’ll see stuff like this all the time:
So - what are the implications of these studies? Read on!
Why are these recent studies so significant?
From a therapeutic standpoint, there is a tremendous amount of confusion regarding what THC is good for, what they're not good for, and what we actually have no evidence for. PTSD is one of the most misunderstood conditions from a public and policy perspective, as it's included on the list of qualifying conditions for medical marijuana in many states. However, this is in spite of the fact that any psychologist or therapist will tell you that using marijuana or THC is a notably bad idea if you have PTSD. Numbing out and experiential avoidance act as the glue that keeps PTSD symptoms going, and by using marijuana to cope with symptoms you are opening the door to becoming addicted on a substance that isn't actually solving the problem. This study is another piece of evidence that THC use does not actually help most people suffering from PTSD, in either the short or long term.
Why is cannabis use a concern for people with PTSD?
Using marijuana to manage symptoms of a chronic condition requires using it daily, and perhaps multiple times daily. This type of daily, consistent use is what builds tolerance and ultimately chemical dependency on addictive products like marijuana. And yes - marijuana is addictive, and there is actually no debate about this in addiction medicine despite what you may hear on social media, or even from many politicians. We've had evidence for decades that marijuana is physiologically addictive, and that once addicted you will have cravings and withdrawal if you try to stop, just like for any other addictive substance. Marijuana is the second most common substance treated in rehab programs after alcohol, and most patients in those programs will tell you that marijuana addiction is a very real problem.
In addition, if you're using an intoxicating and impairing substance every day, there's a higher chance that you will decide to complete regular daily activities while high, which leaves the door open to dangerous circumstances. Another recent study found that for patients using medical marijuana for chronic pain, over 50% said that they'd driven "a little bit high" in the past 6 months, and 20% said they'd driven while "very high" over the past 6 months. Compare this to roughly 4% of the adult population that endorsed driving while high over the past year.
What advice can you offer for therapists whose patients with PTSD are self medicating with cannabis?
The best way to reach patients who are self-medicating with THC for PTSD symptoms is to give them accurate information about the nature of PTSD, and then a full picture of what different paths forward look like. In particular, if a patient with PTSD has not tried one of the three evidence-based modalities that has strong research support (Cognitive Processing Therapy, Prolonged Exposure Therapy, or Eye-Desensitization Movement and Reprocessing), they would be far better off starting there - those therapies can actually solve the root cause of the problems that are fueling the PTSD symptoms, as opposed to just treating the symptoms and not getting at the core issue. In addition, you can also point out to the patient directly how the marijuana is not actually solving the problem, and does not represent a viable path forward, rather just a way to tread water and experience some relief at the expense of longer-term problems. In most cases the patient intuitively knows this, but continues to use marijuana because they feel it is their only option for relief. Presenting an alternative path forward is key.
What else should therapists know about the subject?
It's helpful to be up-to date on what symptoms medical marijuana has been shown to effectively treat, and which it has not. A great resource for this is this 2018 systematic review of systematic reviews of medical cannabinoids, as well as this 2019 scoping review of systematic reviews. It's also helpful to acquaint yourself with medications that react poorly to THC in the body, as your patient may not have disclosed his or her THC use to his medical care team, which could affect their prescribing choices.