Just want to add to my above post.....
I don't want to sound like I am trying to recommend anything, sorry about that, but I do think that it is a good idea to taper any sort of drug addiction.... even milder addictions like marijuana. Quitting cold turky is too harsh, and I believe that pushes people to relapse.
Prescription methamphetamine (desoxyn) doesn't seem much different from prescription amphetamine (adderall). I would argue that there very little difference. Most meth addicts find that adderall is not that strong because they are used to smoking or shooting it, which provides an instant high. When taking amphetamine orally, it takes a while to peak on it, maybe 3 or 4 hours. So there is not the same euphoric rush....so it is the route of ingestion that is important. Taking any drug orally won't be as addictive as taking smoking or shooting it. This is especially seen with nicotine addiction. Cigarette smokers often have trouble switching to nicotine gum because it doesn't provide that instant buzz that cigarettes do.
So, in terms of addictive routes of administration:
Shooting>Smoking>Snorting>Swallowing
I have known some recreational cocaine users who were able to control their use, but once they get into smoking crack, their use turns into a serious addiction. I have even read about some animal based study that said rats, when given the opportunity in a lab setting, that rats will continue to inject amphetamine repeatedly until they die, but they won't eat amphetamine to the same extent.
Anyways, I am not recommending to switch from smoking meth to snorting or swallowing it, but I would think that it would be somewhat less addicting as the rush would be less pronounced.....just my two cents.