. Ibogaine is another psychedelic that has gained the attention of scientists. This is an alkaloid that can be found in the root bark of the Tabernanthe iboga
plant, growing in West central Africa. As early as 1962 the substance was used in trials to overcome heroin addiction. But further investigation was made difficult by a statutory ban in many countries. In Brazil however, ibogaine is not an illegal substance, allowing research to continue. A group of scientists from the University of São Paulo, led by Eduardo Schenberg, retrospectively evaluated data from a private clinic in Curitiba, which treated patients with pure ibogaine HCl in a professional environment and as part of a larger psychotherapeutic program 
. The patients in the study were addicts to alcohol, cannabis, cocaine, and/or crack cocaine. The researchers concluded that 61% of these patients were still abstinent after five to eight months, and that none of them experienced long-lasting negative side effects. Repeated sessions (two or three times) appeared to be especially effective.
Using ibogaine in the treatment of drug addiction is not without risks however. The substance can cause serious arrhythmia, which has led to several fatalities in the past. But according to Schenberg et al., most of these cases were probably due to a pre-existing heart disorder (e.g. “long-QT-syndrome”, a condition causing severe irregular heartbeat). Moreover, the ibogaine or iboga extracts in those cases were often used without quality control and without the supervision of trained and qualified medical staff. Using other psychoactive substances and certain prescription drugs shortly before the ibogaine ingestion can also cause adverse effects. For that reason, the clinic in which this study took place implemented a protocol to ensure that patients are abstinent at least thirty days before the ibogaine is administered. If this is observed and sessions are accompanied in a professional way, then ibogaine can probably be a good aid in the treatment of addiction, according to the researchers. They admit however that more research is necessary, also into the potential adverse effects of ibogaine on the heart.
 Johnson et al. (2014) and Krebs & Johansen (2012)
 Schenberg et al. (2014)
Schenberg, E. E., de Castro Comis, M. A., Rasmussen Chaves, B. & da Silveira, D. X. (2014). Treating drug dependence with the aid of ibogaine: A retrospective study. Journal of Psychopharmacology, 28(11), 993-1000. [Abstract]
Krebs, T. S. & Johansen, P. Ø. (2012). Lysergic acid diethylamide (LSD) for alcoholism: meta-analysis of randomized controlled trials. Journal of Psychopharmacology, 26(11), 994-1002. [Abstract]
Johnson, M. W., Garcia-Romeu, A., Cosimano, M. P., & Griffiths, R. R. (2014). Pilot study of the 5-HT2AR agonist psilocybin in the treatment of tobacco addiction. Journal of Psychopharmacology, 28(11), 983-992. [Abstract]