You've found a great place to discuss this!
Actually, that's quite a loaded question you've asked, but certainly a good one.
I wouldn't even know where to begin to be honest......there's so many factors involved. The question regarding our bodies building up a tolerance to our meds......in my case YES, especially the strong pain meds (opioids)...which calls for higher doses, which eventually leads to more side effects (depleted hormones, increased liver enzymes....) so, in my case I felt as tho I had literally been thru the gammet of medicinal options, so I opted for a more invasive procedure and had a dorsal column stimulator implanted.

Since you've been taking your current meds for several years, and in just a short time have noticed a substantial spike in your pain level, I would probably look into other factors outside of the medication issue in the attempt at finding the underlying issue before making any drastic changes in medication. Make sure you follow Doc's orders if you DO change meds....tapering will be an important factor (which I'm sure you already know)...

There are so many very knowledged folks here who can point you in a direction of perhaps targeting some underlying issues.......
Meanwhile, take a look at the 'stickies' at the top of this page......it's FULL of valuable information..... It really is worth it to do the 'detective work' involved, rather than just hoping for the right medicine. It's a huge undertaking and a process of elimination.....but there really is no possible way to compare one's PN battle with another's.

Hopefully others will be along and share suggestions and experiences.

Do stick around......you'll find we do have one thing in common --- the desire for a better quality of life.....
So much to learn, but we do stick together

Best Wishes
Rae