storage in your tissue--and more importantly, the half-life of Methadone is (on average) 25 hours (13-47 hours),
with peak absorption in 4 hours. However,
Methadone lasts for approximately 25 hours for the average patient, BUT there are a few of us who have taken it every 8 hours to reduce the amount of Methadone needed (for pain management), by reducing the zig-zag effect of depleting and replenishment of Methadone within our tissues.