"In Russia, substitution therapy is forbidden by law, and naltrexone is the only available pharmacotherapy for heroin dependence. Due to the lack of alternatives to naltrexone and stronger family control of compliance (adherence), naltrexone is more effective for relapse prevention and abstinence stabilization in Russia than in Western countries. Long-acting, sustained-release formulations (injectable and implantable) seem particularly effective compared with oral formulations."

Source

Krupitsky, Evgeny, Zvartau, Edwin, and Woody, George, "Use of Naltrexone to Treat Opioid Addiction in a Country in Which Methadone and Buprenorphine Are Not Available," Current Psychiatry Reports, 2010 October; 12(5): 448–453. doi:10.1007/s11920-010-0135-5.
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