In a model of maternal separation, reduced CB1 expression was found to be associated with sleep reduction while oleamide ameliorated sleep in adult rats (Reyes Prieto et al., 2012).
In the same model of maternal separation but not in wild type rats, sleep was shown to be restored by administration of 2-AG, demonstrating that the endocannabinoid system is involved in sleep processes (Pérez-Morales et al., 2014).
In rats, sleep can be induced via activation of CB1 receptors in the endopeduncular nucleus whereas its blockage promotes insomnia-type symptoms (Méndez-Díaz et al., 2013).
In a rat model with in vivo microdialysis, anandamide was shown to increase sleep through mediation of CB1 receptors (Murillo-Rodriguez et al., 2003).
CBD may function as a suppressor of anandamide uptake through TPRV1, proposing a role in sleep (Bisogno et al., 2001; Mechoulam et al., 1997).
In an EEG experiment with rats, the CB1 cannabinoid receptor antagonist SR 141716A exhibited arousal-enhancing activities, proposing again that the endocannabinoid system is involved in sleep (Santucci et al., 1996).
In rats, VDM 11 (inhibitor of ANA cellular uptake) was found to improve sleep and increase c-Fos expression in sleep-related brain areas (Murillo-Rodríguez et al., 2008).
People with insomnia had decreased time to fall asleep upon THC administration compared to controls (Cousens and DiMascio, 1973).
In rats, anxiety-induced REM sleep alteration may be blocked by CBD (Hsiao et al., 2012).
Nabilone (a synthetic cannabinoid) was reported to produce positive effects in treating sleeping problems related to PTSD (Cameron et al., 2014).
In one study, 81 and 14 participants reported that they use cannabis to treat insomnia and reduce nightmares, respectively (Belendiuk et al., 2015).
One study involved 409 people with insomnia to assess the effect of cannabis consumption via an app. It was shown that there is a connection between medical cannabis consumption and improvements in perceived insomnia (Vigil et al., 2018).
Vigil, Jacob M., et al. “Effectiveness of raw, natural medical cannabis flower for treating insomnia under naturalistic conditions.” Medicines 5.3 (2018): 75.