"To conclude, it must be stated that heroin treatment involves a somewhat higher safety risk than methadone treatment. This is mainly due to the intravenous form of application. The rather frequently occurring respiratory depressions and cerebral convulsions are not unexpected and can easily be clinically controlled. Overall, the mortality rate was low during the first study phase, and no death occurred with a causal relationship with the study medication. Compared to much higher health risks related to the i.v. application of street heroin, the safety risk of medically controlled heroin prescription has to be considered as low."
Naber, Dieter, and Haasen, Christian, Centre for Interdisciplinary Addiction Research of Hamburg University, "The German Model Project for Heroin Assisted Treatment of Opioid Dependent Patients -- A Multi-Centre, Randomised, Controlled Treatment Study: Clinical Study Report of the First Study Phase," January 2006, p. 150.