GENERIC NAMES: Sulfamethoxazole and trimethoprim; cotrimoxazole

BRAND NAMES: Bactrim; Septra

DRUG CLASS AND MECHANISM: Cotrimoxazole is a combination of sulfamethoxazole and trimethoprim in a ratio of 5:1 or 1:2. Trimethoprim and sulfamethoxazole both block the production of folic acid, a necessary chemical for both bacteria and humans, and each is an effective antibiotic when used alone. For more information on the individual drugs, please visit their respective sites in the Pharmacy section. Cotrimoxazole was approved by the FDA in 1973.

PRESCRIPTION: yes

GENERIC AVAILABLE: yes

PREPARATIONS: Tablets containing 160mg trimethoprim and 800mg sulfamethoxazole (Bactrim, Septra); 320mg trimethoprim and 160mg sulfamethoxazole (Bactrim DS; Septra DS).

STORAGE: The tablets should be kept at room temperature, 15-30°C (59-86°F).

PRESCRIBED FOR: Cotrimoxazole is used for urinary tract infections, respiratory tract infections, middle ear infections, for prevention of infections due to pneumococcus in transplant recipients, for the treatment or prevention of Pneumocystis carinii pneumonia, chancroid, and prevention of toxoplasma encephalitis in patients with AIDS.

DOSING: Cotrimoxazole is taken two to three times daily, with or without meals, depending on the type and severity of infection. It should be taken with 6 to 8 ounces of liquid to prevent crystals from forming in the urine. Persons with advanced kidney disease may require lower doses.

DRUG INTERACTIONS: Please read articles sulfamethoxazole and trimethoprim.

PREGNANCY: The effects of the sulfonamide class of antibiotics, including sulfamethoxazole, on the fetus have not been adequately studied. Physicians may elect to use cotrimoxazole if its benefits are deemed to outweigh potential risks. On the other hand, use of sulfonamides near term (that is, by the ninth month) may cause bilirubin to be displaced from proteins in the infant's blood. Displacement of bilirubin can lead to jaundice and a dangerous condition called kernicterus in the infant. For this reason, cotrimoxazole should not be used near term in pregnant women.

NURSING MOTHERS: Please read the sulfamethoxazole and trimethoprim articles.

SIDE EFFECTS: Please read the sulfamethoxazole and trimethoprim articles.

Printer-Friendly Format

|

Email to a Friend

From the Doctors at MedicineNet.com

Urinary Tract Infection In Adults - Read about urinary tract infection (UTI) causes (in men, women), symptoms, treatment (antibiotic medicine), recurrent bladder infection prevention (cranberry) and FAQ. Source:Government Otitis Media - Learn more about otitis media and how this acute or chronic middle ear infection, that mostly affects children, is caused, diagnosed and treated on MedicineNet.com Source:MedicineNet Toxoplasmosis - Get the facts on toxoplasmosis infection during pregnancy treatment, diagnosis, symptoms, prevention and causes. Learn how it is transmitted (cat feces, handling uncooked meat). Source:MedicineNet Read 23 more sulfamethoxazole and trimethoprim related articles ... Health Tip: Traveling During Pregnancy Health Tip: Keeping the Caregiver Healthy Lowering Dietary Fat May Help Prevent Prostate Cancer Acne Drug Prevents Tissue Damage From Emphysema Hot Flashes Reduced by Neck Injection Health Highlights: May 15, 2008 Embryonic Pathways Induce Stem Cell Traits New Laser Approved to Treat Psoriasis Genes Play Part in Prostate Cancer Among Races Salmonella Outbreak Linked to Dry Dog Food

Back to Medications Index

Last Editorial Review: 12/31/1997