To make a long story short, my mother bought a drug test ( for my brother)from the store that tested for a whole bunch of different drugs. Well it came back positive for Opiate and Oxycodone. I am not sure why they were in two different catergories, I thought Perc,Oxys,Heroin etc. were all considered opiates. WHats the difference between them? And since they both came back as positive, what could that be?