What are the recommended antibiotics (Abx) for treating uncomplicated cystitis?

Recommended Antibiotics for Uncomplicated Cystitis

Nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5 days) is the preferred first-line treatment for uncomplicated cystitis due to its minimal resistance patterns and high efficacy. 1, 2

First-Line Treatment Options

• Nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5 days) is recommended as first-line therapy with clinical cure rates of 88-93% and bacterial cure rates of 81-92% 1
• Trimethoprim-sulfamethoxazole (160/800 mg twice daily for 3 days) is appropriate first-line therapy only when local resistance rates of uropathogens are known to be <20% or the infecting strain is confirmed susceptible 1, 3
• Fosfomycin trometamol (3 g single dose) is another first-line option with minimal resistance, though it may have slightly inferior efficacy compared to multi-day regimens 1, 2
• Pivmecillinam (400 mg twice daily for 3-7 days) is recommended in regions where available (primarily European countries, not available in North America) 1, 4

Alternative Treatment Options

• Fluoroquinolones (ciprofloxacin, levofloxacin, ofloxacin) are highly effective in 3-day regimens but should be reserved as alternative agents due to their propensity for collateral damage (promoting resistance) 1, 5
• β-Lactam agents (amoxicillin-clavulanate, cefdinir, cefaclor, cefpodoxime-proxetil) in 3-7 day regimens should be used only when first-line agents cannot be used, as they generally have inferior efficacy and more adverse effects 6, 1
• Other β-lactams like cephalexin are less studied but may be appropriate in certain settings when first-line options cannot be used 6, 5

Treatments to Avoid

• Amoxicillin or ampicillin should not be used for empirical treatment due to poor efficacy and high prevalence of antimicrobial resistance worldwide 6, 1

Treatment Algorithm for Uncomplicated Cystitis

1. First choice: Nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5 days) 1, 7
2. Second choice: Fosfomycin trometamol (3 g single dose) 2, 8
3. Third choice: Trimethoprim-sulfamethoxazole (160/800 mg twice daily for 3 days) if local resistance <20% 1, 3
4. Alternative options (when first-line agents cannot be used):
   • Fluoroquinolones (3-day regimen) 1, 7
   • β-Lactams (3-7 day regimens) 6, 5

Special Considerations

• For patients with sulfa allergies: Use nitrofurantoin or fosfomycin as first-line options 2, 5
• For patients with penicillin allergies: Nitrofurantoin, fosfomycin, and trimethoprim-sulfamethoxazole (if no sulfa allergy) are appropriate options 2
• For patients with both sulfa and penicillin allergies: Nitrofurantoin and fosfomycin are the preferred options 2

Common Pitfalls to Avoid

• Using fluoroquinolones as first-line therapy despite their high efficacy, as this promotes resistance to these important agents needed for more serious infections 1, 9
• Prescribing trimethoprim-sulfamethoxazole empirically in areas with high resistance rates (>20%) or in patients with sulfa allergies 1, 7
• Using amoxicillin or ampicillin empirically due to high resistance rates 6, 1
• Prescribing treatment durations longer than recommended (common mistake seen in 71-82% of prescriptions for common antibiotics) 9

Comparative Efficacy

• Nitrofurantoin has shown similar clinical cure rates to ciprofloxacin (93% vs 95%) and trimethoprim-sulfamethoxazole (93% vs 95%) 1
• Fosfomycin demonstrates clinical cure rates of approximately 90%, but microbiological cure rates may be lower (78%) compared to nitrofurantoin (86%) 1
• Trimethoprim-sulfamethoxazole shows significantly reduced efficacy against resistant organisms (clinical cure rates of 41-54% for resistant strains vs 84-88% for susceptible strains) 1, 10