Roxicodone is made out of oxicodone hydrochloride - it is a immediate release form of oxycodone. http://www.healthsquare.com/drugs/111891.htm What we usually think of oxycodone is oxycontin - a sustained release form of the drug. If what you're referring is oxycontin 20 mgs - then it is stronger than roxicodone 30 mgs since its designed to last for much longer; that is, there's much more pain killer in that pill.
However in short term release Roxicodone 30 mgs should be stronger but it doesn't last as long.
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