RT Journal A1 Fraser AD T1 MEthadone and theories of addiction JF JAMA JO JAMA YR 1989 FD April 7 VO 261 IS 13 SP 1879 OP 1879 DO 10.1001/jama.1989.03420130041011 UL http://dx.doi.org/10.1001/jama.1989.03420130041011 AB To the Editor. —  In the article by Dr Dole1 in the November 25 issue of JAMA, it was stated that clinical success in the rehabilitation of heroin addicts requires stabilization of the blood level of methadone in a pharmacologically effective range (150 to 600 ng/mL).Other investigators have studied plasma concentrations of methadone and have attempted to establish whether a threshold serum concentration or therapeutic window exists for methadone in the treatment of opiate dependency.2-7 All these studies measured the total serum concentration of methadone (protein-bound fraction and free fraction). Olsen8 studied the binding of tritiated l-methadone with solutions of purified human γ-globulin and human plasma. γ-Globulin bound 13% to 17.5% of the methadone and human plasma bound 83.7% to 87.3%. Since the maximum albumin binding was 43.8%, the author thought that other proteins probably bound methadone as well.Romach et al9 reported the