What is the difference between hydrogen and oxygen in codone pain pills?

See below: Do you mean hydro(codone) compared to oxy(codone)? Hydrocodone is a semi-synthetic opioid derived from either of two naturally occurring opiates: Codeine and thebaine. Oxycodone is an analgesic medication synthesized from poppy-derived thebaine. Hydrocodone is: 4, 5a-epoxy-3-methoxy-17-methylmorphinan-6-one. Oxycodone is: (5r, 9r, 13s, 14s)-4, 5α-epoxy-14-hydroxy-3-methoxy-17-methylmorphinan-6-one.

Hydro vs oxycodone: I think you mean hydrocodone and oxycodone. They are different but related compounds both of which are classified as an opiate. They are approximately equal in strength (percocet is not necessarily stronger). Some people have better pain relief with one or the other. Some people just have fewer side effects with one or the other. Be careful not to take either one for more than a few days.