The Safety of Methadone
From: Chapter 3: The Fundamentals of Methadone Maintenance Treatment, in Methadone Maintenance: A Counsellor's Guide to Treatment (© 2003).
Compared with many other prescribed drugs, methadone is notable for its lack of long-term adverse effects.
Studies of the long-term administration of methadone have confirmed that it is a medically safe drug (Novick et al., 1993). Methadone, taken at a properly adjusted dose, does not impair psychomotor performance (e.g, reaction time and attention span) or intellectual capacity.
Methadone has also been used successfully in treating opioid-dependent pregnant women since the early 1970s, and there is consensus that methadone can be safely administered during pregnancy with little risk and significant potential benefits to both the mother and infant (U.S. Department of Health and Human Services, 1995).