“…Early-stage clinical trials of psilocybin for nicotine dependence (Johnson et al, 2014) and alcohol dependence (Bogenschutz et al, 2015) have recently been completed, and further trials are currently under way. Observational studies have suggested that sacramental use of plant materials containing classic hallucinogens (peyote, containing mescaline, or ayahuasca, containing DMT) suggests that these practices are associated with decreased disordered use of substances and few if any detrimental effects (Albaugh and Anderson, 1974b;Barbosa et al, 2012;Doering-Silveira et al, 2005;Fabregas et al, 2010;Garrity, 2000;Halpern et al, 2005;Halpern et al, 2008;Kunitz and Levy, 1994;Lu et al, 2009;Roy, 1973). Ayahuasca and ibogaine are being used to treat addictions in many retreat centers and treatment programs in Latin America and the Caribbean, but efficacy studies have not been done.…”