The endocannabinoid system has been shown to be implicated in the extinction and consolidation of aversive memories (Chhatwal, Davis, Maguschak, & Ressler, 2005; Marsicano et al., 2002; Pamplona, Bitencourt, & Takahashi, 2008; Shoshan & Akirav, 2017)

2-AG in the amygdala modulates stress resilience, which can modulate the response to trauma (Bluett et al., 2017)

Patients with PTSD have shown changes in plasma concentrations of endocannabinoids as well as increased CB1 receptors (Hauer et al., 2013; Hill et al., 2013; Neumeister et al., 2013)

Due to the emotional modulation properties of the endocannabinoid system, it has been proposed as a target to treat PTSD (Trezza & Campolongo, 2013).

In fact, Pinna (2018), suggested that endocannabinoids as 2-AG, AEA, PEA and OEA could be helpful to find biomarkers for PTSD, acting mainly in PPAR-α.

PTSD has been linked to cannabis use, which could be used as a coping strategy for PTSD (Bonn-Miller, Babson, Vujanovic, & Feldner, 2010; Bonn-Miller, Vujanovic, Feldner, Bernstein, & Zvolensky, 2007; Bujarski et al., 2012; Cougle, Bonn-Miller, Vujanovic, Zvolensky, & Hawkins, 2011; Kevorkian et al., 2015)

Several studies shown that CBD, as well as THC and synthetic cannabinoids, facilitates extinction of fear memories in rats (Bitencourt, Pamplona, & Takahashi, 2008; Campos, Ferreira, & Guimarães, 2012; Do Monte, Souza, Bitencourt, Kroon, & Takahashi, 2013; Lemos, Resstel, & Guimarães, 2010; Levin et al., 2012; Morena et al., 2018; Resstel, Joca, Moreira, Corrêa, & Guimarães, 2006; Stern et al., 2015)

The effects of cannabinoids on fear extinction would be related to CB1 and 5HT1A receptors (Campos et al., 2012; de Oliveira Alvares, Pasqualini Genro, Diehl, Molina, & Quillfeldt, 2008; Levin et al., 2012; Lin, Mao, Su, & Gean, 2009; Simone, Green, Hodges, & McCormick, 2015)

CBD shows an effect on sleep processes, which could be helpful when targeting sleep disorders related to PTSD (Chagas et al., 2013; Hsiao, Yi, Li, & Chang, 2012)

The effects of CBD in fear memories extinction have been also proved in humans (Das et al., 2013)

The FAAH inhibitor URB597 showed improvement of PTSD related symptoms in rats, which confirms also the link between the endocannabinoid system and PTSD (Fidelman, Mizrachi Zer-Aviv, Lange, Hillard, & Akirav, 2018)

In a pilot study, THC reduced PTSD-related nightmares and other symptoms severity in PTSD patients (Roitman, Mechoulam, Cooper-Kazaz, & Shalev, 2014)

Also, CBD reduced PTSD-related symptoms as anxiety and sleep disorders in a case study of a child who was sexually abused (Shannon & Opila-Lehman, 2016).

In another case report, cannabis use reduced also PTSD-related symptoms as flashbacks and panic attacks (Passie, Emrich, Karst, Brandt, & Halpern, 2012)

In a retrospective study of 80 patients with PTSD, cannabis reduced PTSD-related symptoms (Greer, Grob, & Halberstadt, 2014)

Also, military veterans with PTSD reported that cannabinoids help them to manage PTSD symptoms (Betthauser, Pilz, & Vollmer, 2015)

For a detailed review on the topic see Bitencourt & Takahashi (2018)

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