Best Treatment for Uncomplicated UTI
For uncomplicated cystitis in women, prescribe nitrofurantoin 100 mg twice daily for 5 days as the preferred first-line agent, with fosfomycin 3 g single dose or trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days as alternatives only if local resistance rates are <20%. 1, 2
First-Line Treatment Options for Uncomplicated Cystitis
The choice among first-line agents depends on local resistance patterns and specific patient factors:
Nitrofurantoin (Preferred)
- Dose: 100 mg twice daily for 5 days 1, 2, 3
- Advantages: Minimal resistance rates, low propensity for collateral damage (does not select for multidrug-resistant organisms), and excellent urinary concentration 2, 4
- Key consideration: This agent has emerged as the preferred choice because fluoroquinolones and trimethoprim-sulfamethoxazole cause significant "collateral damage" by selecting for resistant organisms 4
Fosfomycin Trometamol (Alternative)
- Dose: 3 g single dose 1, 2, 3
- Advantages: Convenient single-dose regimen, minimal collateral damage 2, 4
- Limitation: Slightly lower efficacy compared to nitrofurantoin 2
Trimethoprim-Sulfamethoxazole (Conditional Alternative)
- Dose: 160/800 mg twice daily for 3 days 1, 2, 3
- Critical restriction: Use ONLY if local E. coli resistance rates are documented to be <20% 2, 4
- Important caveat: Rising resistance rates globally have demoted this from first-line status in most regions 1, 4
Agents to AVOID for Empiric Treatment
Fluoroquinolones (Reserve for Complicated Cases)
- Ciprofloxacin and levofloxacin are highly efficacious in 3-day regimens but should NOT be used for uncomplicated cystitis 1
- Rationale: High propensity for adverse effects and significant collateral damage (selection of multidrug-resistant organisms) 1, 4
- Reserve these agents for pyelonephritis or documented resistant organisms 1, 2
Beta-Lactams (Use with Caution)
- Amoxicillin-clavulanate, cefdinir, and cefpodoxime have inferior efficacy and more adverse effects compared to first-line agents 1
- Plain amoxicillin or ampicillin should NEVER be used empirically due to very high resistance rates worldwide 1
Treatment for Uncomplicated Pyelonephritis
If the patient has flank pain, fever, or systemic symptoms suggesting pyelonephritis:
Outpatient Oral Therapy
- Fluoroquinolones (if local resistance <10%): Ciprofloxacin 500-750 mg twice daily for 7 days OR levofloxacin 750 mg once daily for 5 days 1
- Trimethoprim-sulfamethoxazole: 160/800 mg twice daily for 14 days (longer duration required) 1
When to Hospitalize
- Patients requiring hospitalization should receive initial IV therapy with fluoroquinolones, extended-spectrum cephalosporins (ceftriaxone 1-2 g daily), or aminoglycosides 1
Special Considerations
When Urine Culture IS Needed
- Men with UTI symptoms (always obtain culture) 3
- Recurrent infections (≥3 per year or ≥2 in 6 months) 2
- Treatment failure or symptoms persisting beyond 48-72 hours 2, 3
- Atypical presentation or suspected resistant organisms 3
- Older adults ≥65 years 2
When Urine Culture is NOT Needed
- Women with typical symptoms (frequency, urgency, dysuria, suprapubic pain) and no vaginal discharge can be diagnosed clinically without testing 3
Common Pitfalls to Avoid
Do not use fluoroquinolones for simple cystitis - this drives antimicrobial resistance for more serious infections 1, 4
Do not assume trimethoprim-sulfamethoxazole is still first-line - resistance rates have risen significantly since older guidelines 1, 4
Do not treat asymptomatic bacteriuria - except in pregnant women or before invasive urologic procedures 2
Do not prescribe antibiotics for longer than necessary - 5 days of nitrofurantoin is as effective as 7-10 day courses 1, 3