Is It Possible/common for Teen Drug Addicts to Go to Detox and Skip Rehab?

I am writing a story for English and my character is a 15 yr old drug addict (I am not assigning a specific drug for her to be addicted to; she does anything that will give her a high) I am trying to figure out how the whole detox/rehab thing would work. I would rather write about her in detox rather than in rehab being taught to stay off of drugs. Any information at all on this would be helpful. =]