I'm sorry, Jovic - this sounds like a rough ride. I can offer a few very small suggestions:
1) Sulfasalazine includes itching as a simple side effect. Sulfamethoxazole/trimethoprim does not. So while it's possible that your itching was because of a sulfa allergy, it's also quite possible that you'd do fine with Sulfamethoxazole/trimethoprim.
2) Do you take a (bacterial) probiotic? It might help get your gut on a better track.
3) Do you use a sinus rinse? I've found it quite helpful, and getting the sinuses to drain properly can be as valuable as the antibiotics.
Good luck!
--Scott