From the Guidelines
Bactrim, also known as trimethoprim-sulfamethoxazole (TMP-SMX), is recommended for the treatment of uncomplicated urinary tract infections (UTIs) for 3 days, as long as local resistance rates do not exceed 20% 1.
Treatment Guidelines
The American College of Physicians recommends short-course antibiotics for UTIs, including TMP-SMX for 3 days, nitrofurantoin for 5 days, or fosfomycin as a single dose 1.
- The choice of antibiotic should be based on local resistance rates and patient-specific factors.
- TMP-SMX is effective against many bacteria that have developed resistance to other antibiotics.
- Common side effects of TMP-SMX include rash, nausea, and diarrhea.
Important Considerations
- TMP-SMX should be avoided in patients with sulfa allergies, certain folate deficiencies, severe liver or kidney disease, or during late pregnancy.
- Regular monitoring may be needed for long-term use due to potential effects on blood cells and kidney function.
- Fluoroquinolones, such as ciprofloxacin and levofloxacin, are highly efficacious in 3-day regimens but have a high propensity for adverse effects and should be reserved for patients with a history of resistant organisms 2, 1.
Dosage and Administration
- The standard adult dose of TMP-SMX is one double-strength tablet (160mg trimethoprim/800mg sulfamethoxazole) taken twice daily for 3 days for uncomplicated UTIs.
- Patients should complete the full course of treatment even if symptoms improve before finishing.
- TMP-SMX should be taken with plenty of water to reduce the risk of kidney stones.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Bactrim Overview
- Bactrim, also known as trimethoprim-sulfamethoxazole, is an antibiotic used to treat various bacterial infections, including urinary tract infections (UTIs) 3, 4, 5, 6, 7.
- It is a combination of two antibiotics: trimethoprim and sulfamethoxazole, which work together to inhibit the growth of bacteria 5, 6.
Effectiveness and Resistance
- Studies have shown that Bactrim is effective in treating UTIs, especially those caused by Escherichia coli 5, 6.
- However, there is a growing concern about the increasing resistance of bacteria to Bactrim, particularly among Gram-negative bacteria 3, 7.
- Resistance rates to Bactrim have been reported to be high, making it less effective as an empiric treatment for UTIs in some communities 3, 7.
Alternative Treatment Options
- Due to the increasing resistance to Bactrim, alternative treatment options are being considered, such as nitrofurantoin, fosfomycin, and pivmecillinam 3, 4, 7.
- These antibiotics have been shown to be effective in treating UTIs, including those caused by resistant bacteria 3, 4, 7.