How long will an 80 mg Oxycontin pill last?

I have a prescription for Oxycontin, I'm supposed to take one 80 mg pill when I need it, and I was wondering if anyone could tell me how long they last? The doctor said there's a time release on them, but I can't remember exactly how long it is - 8 hours, 12 hours? Thank you.

: http://alcoholdrugstreatment.info/how-long-will-an-80-mg-oxycontin-pill-last