Rosa:

  "secreted into milk in varying amounts which approach maternal serum
levels. actual concentrations contraersial. levels may ( but probably not) be
sufficient to prevent withdrawal in nursing infant. one death reported.
considered compatible with breastfeeding under contrained  conditions. aap
approves if maternal does of methadon is less than 20/mg/24hrs. use extreme
caution. monitor for sedation, constipation, agitation or withdrawal. aap
compatable...." p218-219

                           patricia