If you think you have a dental infection, such as an abscessed tooth, I suggest you see a dentist as soon as possible to get a proper diagnosis and a prescription for antibiotics, if required.
Bactrim is a combination of two different antibiotics: sulfamethoxazole and trimethoprim. It normally is not used for dental infections. It is used to treat urinary tract infections and respiratory infections, among other things.
It's very important to use the right antibiotic for the right type of infection. It's also very important to take antibiotics exactly as prescribed and to take the entire amount prescribed.
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