How much time would adderrall stay in my urine. also does roxicodone (oxycodone) really stay in ur system 15-20 days?

Depends: Some drugs accumulate, and a single use has a short period of detection (24 hours), while regular use can be 3-4 days. Oxycodone cannot be found 15-20 days when it is in the form of an immediate release drug. The controlled-release long-acting forms like OxyContin, can be detected for longer (10 days), but still not THAT long. Methadone can stick around for 3-4 weeks when used regularly.