I too have fibromyalgia AND Hep-C.  I was on oxycodone (15 mg x4--but usually took less than that).  Straight oxy doesn't eat up your liver or cause gastric upset/bleeding because it has no acetomenophen.  When the inhumane pain pill laws came into effect I could not find a PCP to write for oxy & I can't afford the $40 copay  & extra tests for a pain specialist.  so, the doc put me on tramadol which then interacted with the trazadone I take for the fibromyalgia sleep disruptions and this caused "seratonin syndrome" (a potentially fatal build up of seratonin).  stopped both tramadol & trazadone causing SEVERE withdrawal for over a week--the first 3-4 days were like what you've seen about heroine withdrawal!.  I'm still dealing with wildly high BP & rapid heart rates   anad have successfully weaned myself off 3 different BP meds (and my #'s aren't any worse than when I was taking them & at least I actually have some energy & brain function to research all this myself instead of continually going to the doc & getting handed my Rx's & more expensive tests that come back negative.  I'm up for the next test of 24 hr. urine to check for a tumor on my adrenal gland (or elsewhere).  See if palin old oxycodone (with out NSAID's) will work for you. Good luck.