I found this, whic seems to be relevant:
"Be very careful, the official "lethal dose" for methadone is 25mg for a non-tolerant adult. This means as little as 25mg of methadone has been known to kill adults with no tolerance to opiates. This is a surprisingly low lethal dosage for many people, but I assure you it is true.
Methadone has a very long half-life, unlike heroin, which is a short-acting opiate. So 36 hours after taking methadone, the user will still have half as much of their initial dose in their system.
Methadone can be a very slow drug to start working, and people are often tempted to take more than they need because they think it isn't working as it should do. In fact, it is just the normal process of absorbtion through their stomach that is causing the delay.
For this reason people who overdose on methadone often actually do so as much as a day or two after they took it."
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i'm sorry you lost your brother -- the disease of addiction takes far too many. sadly, most of the deaths could be avoided if we addicts had the capacity to realize just how much trouble we were in and how badly we needed help. for most of us, by the time we think our feet MIGHT be getting wet, we're already in over out heads.
CATUF
Good lord..if ur serious I'm sorry to hear that (truly)
Bless U