one of the more popular ones right now is Suboxone, but there is plenty of reasons to be wary of Suboxone. It has helped many people, but it is too new to be well understood.
If your son is hooked on anything except heroin (meaning he's not using needles) then he should, in my own opinion, stay far far away from Methadone. most opioids have short half-lives, a few hours or so, but Methadone's half life is 30-40 hours, which is why addiction specialists find it appealing -- it can quell the desire to get high for much longer than other drugs -- but Methadone is insidiously addictive, and unless a person is put on a strict regimen that tapers down after a few weeks or so, they can end up on the drug for years.
Some benzodiazepines are used, like clonazepam. This will likely put him to sleep for 3-4 days, on and off, as he detoxes. When he comes off the drug, the physical cravings are close to gone-- this is different than Suboxone, which has an opioid in it, and Methadone, which is a non-traditional opioid.
From there, he needs psycho social support. Doesn't have to be 12 step, he just needs to re-learn how to be a sober person again, how not to give in to temptation.
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