6-7 hours pain relief is not sufficient analgesia for this type of medication. If the dose you're on isn't holding your pain for 12 hours, then the dose obviously is not high enough for you. There is virtually no upper limit to the dose of Oxycontin that a doctor can order . Rarely will they go over 100mgs twice daily for pain not connected with cancer for some reason, but at 20mgs you certainly have a lot of leeway yet.

I've been on 15mgs twice daily for about a year now, and my doctor told me to try different doses to try and regulate my own pain control. He suggested dropping to10mgs if I had days where there wasn't much pain, but increasing up to 20mgs with bad days. I rarely have to do that as 15mgs seems to be just right for me at the moment, but then I do have the added benefit of quick release Oxycodone for those occassional rotten days.

I'd like to offer you more, but I think all you can do is ask the doctor why you're only getting a few hours pain relief from a medication that is meant to last 12 hours, and suss him out whether or not he's willing to increase the dose.

I don't believe (in your case) your doctor is prescribing the medication as it's meant to be used, and by that I mean to gradually increase the dose until you're happy with the pain management that's achieved.