Yikes!!! That's a LOT of meds!!! They may not have interactions, per se, but so many meds cannot be good!
I, too, have a bad back, 3 levels fused, with 1 not repaired above the fusion. Due to some bad surgery, I have permanent nerve damage in the spine, causing me to have 23% of the feeling on the right as the left.
They removed the screws, and eliminated much of the pain, but I still have sciatic & piriformis nerve pain.
I got off of as much medicine as I possible could. I was taking oxycodone, gabapentin, and fentynal patches, 2 muscle relaxers, sleeping pills, and anti depressants. The idea was to feel better... since I always felt the pain, and felt "muddy." Especially gabapentin. I ONLY take Ocycontin 20mg x3 a day, 4mg Tizanidine (muscle relaxer) 1xdaily as needed, and Lidoderm patches. I also use a TENS unit, sometimes for hours! Am I still in pain? YES!! But it is livable!! I have my mind, can think and do for myself.. things I could not do while on all those meds..