What are the recommended antibiotics for treating uncomplicated cystitis?

Recommended Antibiotics for Uncomplicated Cystitis

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

First-Line Treatment Options

• Nitrofurantoin monohydrate/macrocrystals (100 mg twice daily for 5 days) has clinical cure rates of 88-93% and bacterial cure rates of 81-92%, with minimal resistance development 1
• Fosfomycin trometamol (3 g single dose) is an appropriate alternative first-line option with minimal resistance, though it may have slightly inferior efficacy compared to standard short-course regimens 1, 2
• Trimethoprim-sulfamethoxazole (160/800 mg twice daily for 3 days) is appropriate as first-line therapy only when local resistance rates of uropathogens are known to be <20% or the infecting strain is confirmed susceptible 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

Alternative Treatment Options

• Fluoroquinolones (ofloxacin, ciprofloxacin, norfloxacin, levofloxacin) are highly effective in 3-day regimens but should be reserved as alternative agents due to their propensity for promoting resistance 1, 3
• 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 4, 1
• Other β-lactams like cephalexin are less studied but may be appropriate in certain settings 4

Treatments to Avoid

• Amoxicillin or ampicillin should not be used for empirical treatment due to poor efficacy and high prevalence of antimicrobial resistance worldwide 4, 1

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%) 2
• Trimethoprim-sulfamethoxazole shows significantly reduced efficacy against resistant organisms (clinical cure rates of 41-54% for resistant strains vs 84-88% for susceptible strains) 2

Special Considerations

For Patients with Penicillin Allergy

• Nitrofurantoin remains the first choice for treatment 2
• Fosfomycin trometamol (3 g single dose) is an appropriate second choice 2
• Trimethoprim-sulfamethoxazole (if no sulfa allergy and local resistance <20%) is a third choice 2

For Patients with Renal Insufficiency

• Nitrofurantoin is contraindicated in patients with significant renal impairment (traditionally CrCl <60 ml/min), though some recent evidence suggests it may be effective in patients with CrCl 30-60 ml/min 5
• Trimethoprim-sulfamethoxazole requires dose adjustment in renal impairment 6

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, 3
• Prescribing trimethoprim-sulfamethoxazole empirically in regions with high resistance rates (>20%) 1, 7
• Using amoxicillin or ampicillin empirically due to high resistance rates 4, 1
• Failing to consider local resistance patterns when selecting empiric therapy 1, 3