CNR1 and Respiratory insufficiency due to muscle weakness: While reports of direct CNS administration of the dual CB1/CB2R agonist, WIN 55212-2, produced respiratory depression (Pfitzer et al., 2004), imagining studies for cannabinoid receptors have been inconsistent in confirming receptor presence and exact concentration levels in brainstem respiratory nuclei (Ryberg et al., 2007; Huxtable et al., 2010; Lorea-Hernandez et al., 2016).