“…Conversely, ethnicity, polysubstance use, concurrent tobacco cessation, family history of substance use, and certain genetic polymorphisms were shown to moderate cannabis withdrawal (Agrawal et al, 2008; Ehlers et al, 2010; Gizer et al, 2013; Haughey, Marshall, Schacht, Louis, & Hutchison, 2008; Preuss et al, 2010; Vandrey et al, 2008). The most common symptoms of withdrawal can be clustered into symptoms of weakness or symptoms of anxiety and depression (Hasin et al, 2008), with restlessness, appetite change, irritability, sleep problems and craving being most severe (Milin, Manion, Dare, & Walker, 2008; Vandrey et al, 2008; Allsop, Norberg, Copeland, Fu & Budney, 2011). …”