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Bactrim Uses
Bactrim is used for treating various types of bacterial infections, including urinary tract infections, traveler's diarrhea, and ear infections. The antibiotic is also approved to prevent Pneumocystis carinii pneumonia in people with weakened immune systems at risk for the infection. Healthcare providers may also occasionally recommend off-label uses of the drug, such as for treating acne and preventing (instead of treating) various types of infections.
Bactrim® (sulfamethoxazole/trimethoprim) is an antibiotic used to treat a variety of different infections. In particular, Bactrim is approved to treat the following infections:
- Urinary tract infections (UTIs), such as bladder infections
- Ear infections
- Acute worsening of chronic bronchitis
- Shigellosis (a form of dysentery)
- Traveler's diarrhea
- A certain type of pneumonia known as Pneumocystis carinii pneumonia.
Bactrim is also approved to prevent Pneumocystis carinii pneumonia in people with weakened immune systems at risk for the infection (such as people with HIV or AIDS).
Bactrim is approved for treating the infections listed above only when they are caused by certain types of bacteria. Not all bacteria will respond to Bactrim. Even among the types of bacteria that do respond to Bactrim, some strains may have become resistant and may have different resistance patterns in different regions in the country. This means that some bacteria may be susceptible to Bactrim in certain parts of the country but not in others.
It is important to remember that Bactrim is completely ineffective for treating viral illnesses (such as the common cold or the flu).
In some situations, your healthcare provider may perform certain tests to see if your particular infection is susceptible or resistant to Bactrim. In other situations, your healthcare provider may decide to try Bactrim without such tests.
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD



