most likely even w/o oxy use u would still be losing hair. The only thing difference might be the speed of loss. If you aren't taking care of yourself as well as you would if u weren't using then u will lose the hair faster. But most likely hair loss is inevitable for you. It's in your genes and there isn't much u can do about it other than implants or maybe rogaine.
As the previous poster said, take good care of your physical state. Eat well and get all ur vitamins to slow down the process as much as possible.