I've had a bunch of sinus infections over the last year. Amoxicillin doesn't help at all. The stuff's probably resistant. One doc I knew a few years ago said the only med that gets to sinus infections is sulfa drugs.
The most recent one was a doozey. I tried the netti pot, saline rinses, saw PCP who prescribed Bactrim. I nearly went to the ER with the pain, red mask across cheeks and nose. I got an appt with ENT for 2 weeks later. I had a few days relief with Bactrim, but then it came back. My allergist put me on diflucan in case it was yeast or mold. That also seemed to help for a few days. I was prescribed bactroban ointment, which I melted 3 tubes in 45 cc water about 30 sec in microwave (to release it from the parafin base), then put it back into the spray bottle. That seemed to help a few days too. But it all never ended. I stopped all the meds because they didn't really work. A few days later I felt better but still had the headache. Then the ENT looked, wasn't impressed, said go see a neurologist. Aaaaagh! Face still red across nose. Keeping nose from dripping with Rx antihistamine nasal spray. It's not a cure, but I can function. I'll see neuro in a few weeks, soonest available appt.
My allergist and I discussed articles we'd read about bacterial plaque building up in sinuses. ENT said he didn't know much about that. Il think my sinus tissues swell up around my deviated septum (car wreck), and this is how the infection takes hold. Steroid spray just doesn't go far enough in to open it up. Spray antibacterial doesn't go far enough, and hanging head upside down doesn't work either.
Keep reading and posting. We'll beat this gunk yet.