Antibiotics only work for bacterial infections. Sore throats are usually caused by irritation from nasal drainage, secondary to allergies or viruses. If you are running a fever of > 102 degrees its possible you may have a bacterial infection. If the back of your throat shows white pustules its possible you may have strep throat. Strep is still pretty succeptible to amoxicillin and that would be the drug of choice. If you are unable to take that then azithromycin or clarithromycin would be the next best choice. Avelox is overkill for strep throat and should be reserved for resistant or hard to treat respiratory infections.