Methadone and its salts are restricted to:
(1) use in treatment, maintenance, or detoxification programs as approved by the Department of Health and Environmental Control, including narcotic treatment programs operating pursuant to Section 40-43-72.
(2) dispensing by a hospital for analgesia, pertussis, and detoxification treatment as approved by the Department of Health and Environmental Control.
(3) dispensing by a retail pharmacy for analgesia as provided for by R. 61-4, Section 507.5.