You can get it in pill form by prescription from a pharmacy for pain, or get it illegally on the street. Heroin addicts are given a liquid form at methadone clinics. The pill form is very tricky and has caused many deaths -- apparently people take it thinking it is going to be like any other opiate, but ONE pill can kill an unexperienced user.
There was just a true crime mystery show on this week about a methadone overdose that killed a young woman while on a cruise with her boyfriend.
The girl's mother simply couldn't find out how it got into her system, as she was very vehemently anti-drugs.
As things unraveled, it turned out the BF had put his methadone (evidently, he was getting it for drug treatment - they seemed to imply through a lot of the show that he was "clean") in a NyQuil bottle to take it on the cruise, so they wouldn't question him about it.
So, it was possible she had taken some of the so-called NyQuil accidentally.
Just strange that methadone is all of a sudden becoming a death agent when I hadn't seen much about that before. It was also a factor in a L&O episode I missed most of this week.