• We conducted an open clinical trial of the feasibility of maintaining heroin addicts by administering methadone hydrochloride on Monday through Thursday, methadyl acetate on Friday, and no drug at all on Saturday or Sunday. Sixty-five patients from four participating clinics were randomly assigned to this schedule and another 71 to a daily methadone comparison group. The patient sample consisted of heroin addicts previously stabilized on a maintenance regimen of methadone. The starting dose of methadyl acetate was identical to the previously established dose of methadone but was flexible within limits thereafter. A greater number of patients in the methadyl acetate group failed to complete the full 40 weeks of the study, particularly because they claimed the medication was not holding. Although this particular use of methadyl acetate on Friday to provide a drug-free weekend does not appear to be widely applicable clinically, the fact that at least some patients in the methadyl acetate group tolerated the schedule with little or no illicit drug use or obvious discomfort suggests that the strategy is viable and should not be discarded.
Walter Ling, James C. Klett, Roderic D. Gillis. A Cooperative Clinical Study of Methadyl AcetateII. Friday-Only Regimen. Arch Gen Psychiatry. 1980;37(8):908–911. doi:10.1001/archpsyc.1980.01780210066006