sulfamethoxazole and trimethoprim, Bactrim, Bactrim DS

What is sulfamethoxazole and trimethoprim, and how does it work (mechanism of action)?

Bactrim is a combination of two synthetic (man-made) antibiotics, sulfamethoxazole and trimethoprim. Both drugs reduce the ability of some bacteria to utilize folic acid for growing. Sulfamethoxazole is an anti-bacterial sulfonamide, a "sulfa" drug. It disrupts the production of dihydrofolic acid while trimethoprim disrupts the production of tetrahydrofolic acid. Dihydrofolic acid and tetrahydrofolic acid are forms of folic acid that bacteria and human cells use for producing proteins. Trimethoprim inhibits production of tetrahydrofolic acid by inhibiting the enzyme responsible for making tetrahydrofolic acid from dihydrofolic acid. By combining both drugs, two important steps required in the production of bacterial proteins are interrupted, and the combination is more effective than either drug alone. Bactrim was approved by the FDA in 1973.

What brand names are available for sulfamethoxazole and trimethoprim?

Bactrim, Bactrim DS, Sulfatrim Pediatric

Is sulfamethoxazole and trimethoprim available as a generic drug?

GENERIC AVAILABLE: Yes

Do I need a prescription for sulfamethoxazole and trimethoprim?

Yes

What are the uses for sulfamethoxazole and trimethoprim?

Sulfamethoxazole/trimethoprim is used for treating infections due to susceptible bacteria. Examples include urinary tract infections, flares of chromic bronchitis due to bacteria, middle ear infections, for prevention of infections due to pneumococcus in organ transplant recipients, for the treatment or prevention of Pneumocystis carinii pneumonia, chancroid, and prevention of toxoplasma encephalitis in patients with AIDS.

What are the side effects of sulfamethoxazole and trimethoprim?

Common side effects of sulfamethoxazole/trimethoprim are:

Other side effects include:

Medically Reviewed by a Doctor on 7/13/2016

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