What is the recommended treatment for acute uncomplicated cystitis?

Treatment of Acute Uncomplicated Cystitis

Nitrofurantoin monohydrate/macrocrystals 100 mg twice daily for 5 days is the recommended first-line treatment for acute uncomplicated cystitis in women, offering clinical cure rates of 88-93% with minimal resistance and collateral damage. 1

First-Line Treatment Options for Women

The Infectious Diseases Society of America prioritizes three first-line agents based on resistance patterns and efficacy 1:

• Nitrofurantoin monohydrate/macrocrystals 100 mg twice daily for 5 days is the preferred choice with bacterial cure rates of 81-92% and clinical cure rates equivalent to trimethoprim-sulfamethoxazole (93% vs 95%) 1, 2

• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 3 days should only be used when local E. coli resistance is confirmed to be <20% 1, 3. This threshold is critical because efficacy drops dramatically from 84-88% for susceptible strains to only 41-54% for resistant organisms 1, 3

• Fosfomycin trometamol 3 g as a single dose is an appropriate alternative with approximately 90% clinical cure rates, though microbiological cure rates may be slightly lower (78%) compared to nitrofurantoin (86%) 1, 4

• Pivmecillinam 400 mg twice daily for 3-7 days is recommended in European countries where available, but is not available in North America 1

Alternative Agents (When First-Line Cannot Be Used)

• Fluoroquinolones (ciprofloxacin, levofloxacin, ofloxacin) for 3 days are highly effective but should be reserved as alternatives due to collateral damage and the need to preserve them for more serious infections 1, 3

• β-Lactam agents (amoxicillin-clavulanate, cefdinir, cefaclor, cefpodoxime-proxetil) for 3-7 days have inferior efficacy and more adverse effects compared to first-line options 1

Agents to Avoid

• Amoxicillin or ampicillin monotherapy should never be used empirically due to poor efficacy and high worldwide resistance rates 1

Treatment for Men

Cystitis in men requires fundamentally different treatment than in women and should never be treated with short-course regimens. 5

• Ciprofloxacin 500 mg twice daily for 7 days or levofloxacin 500-750 mg once daily for 7 days is the preferred empiric choice due to excellent prostatic penetration 5

• Fluoroquinolones remain appropriate for male cystitis despite concerns about their use in female uncomplicated cystitis 5

• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 7-14 days is an alternative only when local resistance is <20% or susceptibility is confirmed 5

• Do not use nitrofurantoin 5-day courses, fosfomycin single-dose, or pivmecillinam short courses in men—these are inadequate 5

Special Considerations for Patients with Allergies

For patients with sulfa and penicillin allergies 1:

• Fosfomycin trometamol 3 g single dose is the most appropriate first-line alternative 1

• If fosfomycin is unavailable, consider fluoroquinolones (ciprofloxacin, levofloxacin) for 3 days, recognizing their limitations 1

• For sulfa allergies without cephalosporin cross-reactivity, certain β-lactams (cefdinir, cefaclor, cefpodoxime-proxetil) for 3-7 days could be considered, though they have inferior efficacy 1

Critical Decision Points

When choosing empiric therapy, assess these factors 1, 3:

• Local resistance patterns: Avoid trimethoprim-sulfamethoxazole if local E. coli resistance exceeds 20% 3

• Recent antibiotic use: Patients who used trimethoprim-sulfamethoxazole in the preceding 3-6 months should avoid it due to predicted resistance 3

• Recent travel: Travel outside the United States in the preceding 3-6 months increases resistance risk 3

• Patient allergies and cost considerations 1

Common Pitfalls to Avoid

• Using fluoroquinolones as first-line therapy despite high efficacy—this promotes resistance to agents needed for serious infections 1

• Prescribing 3-day regimens for men—they require 7-14 days of treatment 5

• Relying on hospital antibiograms for community-acquired cystitis—these overestimate resistance rates; use local outpatient surveillance data instead 3

• Extending treatment beyond recommended durations—each additional day carries a 5% increased risk of antibiotic-associated adverse events without additional benefit 3