• Memory tests were administered to 30 patients taking methadone hydrochloride and 31 taking levomethadyl acetate (levo-alpha-acetylmethadol, LAAM) both prior to treatment and after one and three months of continuous treatment. A group of nonopiate using matched control subjects was administered the tests at similar intervals. No statistically significant difference in test performance was found among these groups at any of the three sessions. The methadone and control groups also did not differ significantly in the frequency of subjective reports of decreased memory function. Previous reports of memory deficits during long-term methadone administration may be a result of comparing methadone and control groups at a single point in time and assuming that prior to methadone maintenance the groups were equivalent.
Grevert P, Masover B, Goldstein A. Failure of Methadone and Levomethadyl Acetate (Levo-Alpha-Acetylmethadol, LAAM) Maintenance to Affect Memory. Arch Gen Psychiatry. 1977;34(7):849-853. doi:10.1001/archpsyc.1977.01770190111011