This review included the following 12 comparisons: baclofen versus clonidine, clonidine versus clonidine plus amantadine, clonidine versus buprenorphine, high-dose clonidine versus low-dose clonidine versus symptomatic management, clonidine versus methadone, methadone versus tramadol, methadone versus methadone plus gabapentin, gradual reduction of methadone versus sudden withdrawal of methadone, methadone plus amitriptyline versus methadone, diphenoxylate versus propoxyphene, three different protocols of tincture of opium, and tincture of opium versus methadone. The studies were carried out in three countries, Iran, India, and Thailand. Support from a pharmaceutical company in the form of free provision of medications was reported in only one study.

The evidence is unclear as to whether any of the evaluated medications is more effective than another in the management of opium withdrawal. However, it seems that opium withdrawal symptoms are significant in the first days after discontinuation of opium. All of the assessed medications might be useful in alleviating symptoms. Use of clonidine might result in low blood pressure.