question: I have a sinus infection and have great success being treated once a year with azithromycin...tonight a doctor prescribed a a tetracycline antibiotic by the name of doxcycline. I am disheartened by the specific conditions of taking this medicine and by the precaustions and side effects possible, and upon research, have not found any conclusive evidence that this antibiotic is commonly used for sinusitis. Your take...?