Treatment Duration for Uncomplicated UTI
For uncomplicated UTIs in women, treat with short-course antibiotic therapy: nitrofurantoin for 5 days, fosfomycin as a single 3-gram dose, or trimethoprim-sulfamethoxazole for 3 days. 1
First-Line Antibiotic Durations in Women
The recommended treatment durations vary by agent but all fall within the short-course category:
- Nitrofurantoin monohydrate/macrocrystals: 100 mg twice daily for 5 days 1, 2
- Fosfomycin trometamol: Single 3-gram dose 1, 2
- Trimethoprim-sulfamethoxazole: 160/800 mg twice daily for 3 days (only if local resistance <20%) 1, 2
- Trimethoprim alone: 100 mg twice daily for 3 days 2
Evidence Supporting Short-Course Therapy
Three-day antibiotic therapy achieves similar symptomatic cure rates compared to 5-10 day regimens (RR 1.06,95% CI 0.88-1.28 short-term; RR 1.09,95% CI 0.94-1.27 long-term), while causing significantly fewer adverse effects (RR 0.83,95% CI 0.74-0.93) 3. The AUA/CUA/SUFU guidelines emphasize treating with "as short a duration of antibiotics as reasonable, generally no longer than seven days" for recurrent UTI patients experiencing acute cystitis 4.
Treatment Duration in Men
Men with uncomplicated lower UTI require 7 days of treatment with first-line agents (trimethoprim, trimethoprim-sulfamethoxazole, or nitrofurantoin) 2. This longer duration compared to women accounts for potential subclinical prostatic involvement that cannot always be clinically excluded 5.
Important Caveats
Do not confuse uncomplicated cystitis with complicated UTI or pyelonephritis, which require longer treatment:
- Complicated UTI/Pyelonephritis in women: 7-14 days of therapy 4
- Complicated UTI in men: 14 days when prostatitis cannot be excluded 1
- Febrile UTI: 5-7 days of fluoroquinolones (in low-resistance areas) or 14 days of trimethoprim-sulfamethoxazole if susceptible 6
Obtain urine culture before treatment in men, older adults (≥65 years), patients with recurrent infections, treatment failures, or atypical presentations 4, 1, 2. For straightforward uncomplicated cystitis in young women with typical symptoms and no vaginal discharge, culture is not routinely needed 1, 2.
Single-dose therapy is less effective than 3-day regimens and should be avoided except for fosfomycin, which is specifically formulated for single-dose administration 3, 7.