Sinus Medication Solution

I have doxycycline left over from a trip to africa. it is used for malaria prevention. i now have a sinus infection that wont go away. i looked up doxycycline on line and saw that it is used for certain infections but sinus was not listed. the articles say that it may be used for other purposes not listed. will it kill a sinus infection?

I was on Z-pak, Clarinex and Nasonex for a sinus infection, as soon as I finished the course of meds, it came back with a vengence. I get chronic sinus infections but this is BY FAR the worst one, it feels like the whole middle of my face is being held by vice grips, it’s borderline unbearable. I’m now on the second day of Avelox but have not been able to get any relief. I’ve tried everything under the sun, saline spray, neti-pot, breathing in lemon/peppermint steam, tapping, different over the counter sinus pain meds. nothing’s working. Is there anything I haven’t tried? I’m desperate for some kind of relief. I’m about ready to break out the vicadin.