Marijuana and other cannabinoids as a treatment for posttraumatic stress disorder: A literature review

Abstract

Posttraumatic stress disorder (PTSD) is common in the general population, yet there are limitations to the effectiveness, tolerability, and acceptability of available first-line interventions. We review the extant knowledge on the effects of marijuana and other cannabinoids on PTSD. Potential therapeutic effects of these agents may largely derive from actions on the endocannabinoid system and we review major animal and human findings in this area. Preclinical and clinical studies generally support the biological plausibility for cannabinoids' potential therapeutic effects, but underscore heterogeneity in outcomes depending on dose, chemotype, and individual variation. Treatment outcome studies of whole plant marijuana and related cannabinoids on PTSD are limited and not methodologically rigorous, precluding conclusions about their potential therapeutic effects. Reported benefits for nightmares and sleep (particularly with synthetic cannabinoid nabilone) substantiate larger controlled trials to determine effectiveness and tolerability. Of concern, marijuana use has been linked to adverse psychiatric outcomes, including conditions commonly comorbid with PTSD such as depression, anxiety, psychosis, and substance misuse. Available evidence is stronger for marijuana's harmful effects on the development of psychosis and substance misuse than for the development of depression and anxiety. Marijuana use is also associated with worse treatment outcomes in naturalistic studies, and with maladaptive coping styles that may maintain PTSD symptoms. Known risks of marijuana thus currently outweigh unknown benefits for PTSD. Although controlled research on marijuana and other cannabinoids' effects on PTSD remains limited, rapid shifts in the legal landscape may now enable such studies, potentially opening new avenues in PTSD treatment research.

Integrating Endocannabinoid Signaling and Cannabinoids into the Biology and Treatment of Posttraumatic Stress Disorder

“…For example, excess, chronic cannabis use has been associated with a reversible downregulation of CB1 receptors in the brain (Ceccarini et al, 2015;Hirvonen et al, 2012), and both animal and human studies have found that excess cannabis use has been associated with impairments in fear extinction (Lin et al, 2008;Papini et al, 2017), possibly related to an impairment in the native functions of the eCB system. This is consistent with some clinical reports that excess cannabis use may be related to more negative, long-term outcomes in PTSD (Boden et al, 2013;Steenkamp et al, 2017;Wilkinson et al, 2016). As such, while cannabis use may provide benefit for some individuals with PTSD, and should be scientifically examined as a potential treatment approach for PTSD, caution should be exerted with respect to the potential adverse effects that could be associated with excess, chronic cannabis use.…”

Posttraumatic Stress Disorder Is a Risk Factor for Multiple Addictions in Police Officers Hospitalized for Alcohol

“…Cannabis use disorder prevalence and severity were not associated with PTSD, which is contrary to prior studies conducted in different populations [44][45][46][47][48]. Vietnam veterans with higher PTSD scores reported a higher frequency of cannabis use [46], and cannabis was hypothesized to help coping with PTSD symptoms such as hyperarousal, emotional distress, and intrusive thoughts of the trauma [45,47,48].…”

“…Vietnam veterans with higher PTSD scores reported a higher frequency of cannabis use [46], and cannabis was hypothesized to help coping with PTSD symptoms such as hyperarousal, emotional distress, and intrusive thoughts of the trauma [45,47,48]. Although prevalence for at-risk gambling was higher in our sample than in the general population (0.3-0.4%) [49], no association was found with PTSD.…”

Endocannabinoid signaling in psychiatric disorders: a review of positron emission tomography studies

“…One small randomized placebo-controlled crossover trial indicated that nabilone, a synthetic analog of Δ 9 -THC, reduced PTSD symptoms in male military personnel compared to placebo [77]. Despite the lack of randomized trials investigating cannabis use for this indication, some states allow the use of medical marijuana to treat PTSD [78,79]. This is concerning given that individuals with PTSD have a substantially increased likelihood of being diagnosed with cannabis use disorder [80].…”