Current Cutoff Levels for Toxicology
Methadone and EDDP are both excreted in the urine of a person taking methadone. Methadone, however, is highly sensitive to urine pH, whereas EDDP is not. Therefore, it is preferable to monitor EDDP in urine for assessing compliance in drug rehabilitation therapy.
Methadone and EDDP can be detected up to 6-7 days after last use.