Friski, I am sorry you are in so much pain.
I hope it leaves you soon. My pain has never been adequately controlled (CFS) so I can imagine, if I multiply that pain a few times, what you must be experiencing. Do you know if it is the acne antibiotics or the RA antibiotics that are the problem? I too have acne and have had several courses of antibiotics for them over the years. I take it your antibiotics are a low-dose long term treatment? Would you perhaps consider something else to treat the acne, as long-term antibiotics might give you long-term exacerbated pain? Things like topical treatments, accutane (although perhaps not as you have RA), different contraceptive pills (I take Dianette to supress the androgen hormones) etc. But I bet you've been through all the options, right?!
Can you try some complimentary methods to give you a little pain relief to use alongside the pain medications? Heat pads, cold compresses, hydrotherapy etc? Also, just double check with your doctor that you are taking as much of your medications as you can, and also ask if you can combine them. I know this may sound a little obvious, but you never know. When I was in some severe pain last year my doctor told me I could actually take more of the medications than was indicated on the box, and that I could take them differently as indicated (timing of doses), which helped a bit. Combining pain medications can sometime make them more effective. And obviously you know not to try this on your own but to ask your doctor for guidance.Hang in there Friski.