Negative Direct Coombs’ Tests in Narcotic Addicts Receiving Maintenance Doses of Methadone

Direct Coombs’ tests (antiglobulin tests) were performed on blood from 103 opiate users prior to methadone maintenance therapy and 67 long-term methadone maintenance patients. No positive tests were observed in either group. Drug urinalyses revealed that all of the methadone maintenance patients were, in fact, taking methadone, as well as other drugs. This result conflicts with a report in which 85% of the methadone maintenance patients had positive direct Coombs’ tests.