Methadone hydrochloride (Diskets®, Dolophine®, Methadose®) is a prescription drug commonly used for treating pain and addiction to certain types of drugs. Compared to other opioids, methadone has the potential to stay in your system for a long time. In fact, the elimination half-life of methadone is anywhere from 8 to 59 hours.
"Half-life" refers to the time it takes for the blood levels of methadone to be reduced by half. This means that every 8 to 59 hours, the level of medication in your blood will drop by 50 percent of the previous level.
With such a wide range of a reported elimination half-life for methadone, it is impossible to say exactly how long the medicine will stay in the body for any particular person. In addition, methadone accumulates in the liver and other tissues, where it is released slowly. This means that it could potentially stay in the system for a long time.
(Click How Long Does Methadone Stay in Your System? for more information on what the half-life of methadone is and how long this drug stays in your system.)