Abstract: | The increased use and abuse of methadone in recent years has posed a problem of both its identification and quantitation in body tissues. Recent development of a radioimmunoassay for methadone appears to have solved the problem. In our hands the assay was extremely sensitive and specific. It also appears to be an excellent tool when quantitative estimates are to be obtained. Although it initially appears to be relatively expensive, the time saved in doing a complete tissue distribution equalizes the cost. It is hoped that other radioimmunoassays currently under development will prove as satisfactory. |