What are the most common antibiotics (abx) for treating cystitis?

From the Guidelines

The most common antibiotics for cystitis are nitrofurantoin (Macrobid) 100mg twice daily for 5 days, fosfomycin (Monurol) as a single 3g dose, and pivmecillinam 400 mg three times a day for 3-5 days, as recommended by the European Association of Urology guidelines in 2024 1.

Key Considerations

• Nitrofurantoin is often preferred as first-line therapy due to its effectiveness against common urinary pathogens like E. coli and low resistance rates.
• Fosfomycin is recommended only in women with uncomplicated cystitis.
• Pivmecillinam is an alternative option for women with uncomplicated cystitis.
• For men, trimethoprim-sulfamethoxazole 160/800 mg twice daily for 7 days is recommended, with fluoroquinolones as an alternative option based on local susceptibility testing.

Treatment Duration

• Uncomplicated cystitis in women: 5 days for nitrofurantoin, 1 day for fosfomycin, and 3-5 days for pivmecillinam.
• Men: 7 days for trimethoprim-sulfamethoxazole.

Important Notes

• Before starting antibiotics, it's essential to confirm the diagnosis with urinalysis showing pyuria and bacteriuria.
• Patients should complete the full course of antibiotics even if symptoms improve quickly, and increase fluid intake to help flush bacteria from the urinary tract.
• These medications work by either inhibiting bacterial cell wall synthesis, protein synthesis, or folate metabolism, effectively eliminating the infection-causing bacteria, as supported by the American College of Physicians in 2021 1 and the Infectious Diseases Society of America in 2011 1.

From the Research

Most Common Antibiotics for Cystitis

• The most common antibiotics prescribed for cystitis are:
  • Fluoroquinolones (51.6%) 2
  • Nitrofurantoin (33.5%) 2
  • Trimethoprim-sulfamethoxazole (TMP-SMX) (12.0%) 2
• First-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis includes:
  • Nitrofurantoin (5-day course) 3, 4
  • Fosfomycin tromethamine (3-g single dose) 3, 4
  • Trimethoprim-sulfamethoxazole (in regions where the prevalence of Escherichia coli resistance does not exceed 20 percent) 5, 4
• Second-line options include:
  • Oral cephalosporins (such as cephalexin or cefixime) 3
  • Fluoroquinolones and β-lactams (such as amoxicillin-clavulanate) 3

Treatment Duration

• The duration of most prescriptions for TMP-SMX, nitrofurantoin, and fluoroquinolones is longer than guidelines recommendations 2
• Older age and presence of diabetes are independently associated with longer treatment duration 2

Resistance and Treatment Options

• High rates of resistance for trimethoprim-sulfamethoxazole and ciprofloxacin preclude their use as empiric treatment of UTIs in several communities 3
• Treatment options for UTIs due to extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriales include nitrofurantoin, fosfomycin, pivmecillinam, fluoroquinolones, and carbapenems 3