20 C.F.R. § 404.1537
By appropriate treatment, we mean treatment for drug addiction or alcoholism that serves the needs of the individual in the least restrictive setting possible consistent with your treatment plan. These settings range from outpatient counseling services through a variety of residential treatment settings including acute detoxification, short-term intensive residential treatment, long-term therapeutic residential treatment, and long-term recovery houses. Appropriate treatment is determined with the involvement of a State licensed or certified addiction professional on the basis of a detailed assessment of the individual's presenting symptomatology, psychosocial profile, and other relevant factors. This assessment may lead to a determination that more than one treatment modality is appropriate for the individual. The treatment will be provided or overseen by an approved institution or facility. This treatment may include (but is not limited to)-
20 C.F.R. §404.1537