The authors followed a cohort of 610 opioid users for 1 year after adm
ission to methadone maintenance. At the end of the year, 52% were on m
ethadone and 48% were off methadone. Among subjects on methadone, days
of intravenous drug use, crime, and needle-sharing decreased markedly
from the month preceding admission to the month preceding the first a
nniversary of admission. Among subjects off methadone, days of these a
ctivities also decreased but the decreases appeared in large part to b
e an effect of increased days of incarceration. Among those on methado
ne, days of productive activity increased markedly. Subjects with move
years of intravenous drug use were more likely to be on methadone at
the end of the year, and subjects under compulsory supervision were le
ss likely to be on methadone. The findings confirm previous reports of
decreased illicit opioid use, decreased crime, and decreased needle r
isk for infection with the human immunodeficiency vine among opioid us
ers who remain on methadone.