Please consult your physician before taking any medication. Genric ingredients: Trimethoprim, Sulfamethoxazole Why is Bactrim prescribed? Bactrim, an antibacterial combination drug, is prescribed for the treatment of certain urinary tract infections, severe middle ear infections in children, long-lasting or frequently recurring bronchitis in adults that has increased in seriousness, inflammation of the intestine due to a severe bacterial infection, and travelers diarrhea in adults. Bactrim is also prescribed for the treatment of Pneumocystis carinii pneumonia, and for prevention of this type of pneumonia in people with weakened immune systems. Most important fact about Bactrim, Sulfamethoxazole, an ingredient in Bactrim, is one of a group of drugs called sulfonamides, which prevent the growth of bacteria in the body. Rare but sometimes fatal reactions have occurred with use of sulfonamides. These reactions include Stevens-Johnson syndrome (severe eruptions around the mouth, anus, or eyes), progressive disintegration of the outer layer of the skin, sudden and severe liver damage, a severe blood disorder (agranulocytosis), and a lack of red and white blood cells because of a bone marrow disorder. Bactrim may also be used for purposes other than those listed here.