What is the recommended treatment for a bladder infection?

Treatment of Bladder Infection (Acute Uncomplicated Cystitis)

For acute uncomplicated bladder infections in women, use first-line antibiotics: nitrofurantoin (100 mg twice daily for 5 days), fosfomycin trometamol (3 g single dose), or trimethoprim-sulfamethoxazole (160/800 mg twice daily for 3 days), with treatment duration of 3-7 days maximum. 1

First-Line Treatment Options

The following agents are recommended as first-line therapy based on their efficacy and minimal collateral damage (resistance selection): 1

• Fosfomycin trometamol: 3 g single dose orally (1 day treatment) - recommended only for women with uncomplicated cystitis 1
• Nitrofurantoin: 100 mg twice daily for 5 days (available as macrocrystals, monohydrate/macrocrystals, or prolonged release formulations) 1, 2
• Pivmecillinam: 400 mg three times daily for 3-5 days 1
• Trimethoprim-sulfamethoxazole: 160/800 mg (one double-strength tablet) twice daily for 3 days 1, 3, 2

Treatment Selection Algorithm

Step 1: Verify this is uncomplicated cystitis - symptoms of dysuria, frequency, urgency without fever, flank pain, or systemic symptoms 1

Step 2: Check local resistance patterns - trimethoprim-sulfamethoxazole should only be used if local E. coli resistance is <20% 1, 4

Step 3: Choose based on patient factors: 1, 2

• For convenience/adherence concerns: Fosfomycin (single dose) 1
• For pregnancy: Avoid trimethoprim in first trimester and last trimester; nitrofurantoin or cephalosporins preferred 1, 5
• For cost considerations: Nitrofurantoin or trimethoprim-sulfamethoxazole typically less expensive 2

Alternative (Second-Line) Agents

Use these only when first-line agents cannot be used due to allergy, resistance, or intolerance: 1, 4

• Cephalosporins (e.g., cefadroxil 500 mg twice daily for 3 days) - only if local E. coli resistance <20% 1
• Trimethoprim alone: 200 mg twice daily for 5 days 1
• Fluoroquinolones: Reserve for situations where first-line agents are contraindicated; should NOT be used routinely for simple cystitis 1, 4, 2

Treatment Duration

Keep antibiotic courses as short as reasonable: 1

• 3-5 days for most first-line agents 1
• Maximum 7 days for uncomplicated cystitis 1
• Single-dose regimens (fosfomycin) have higher short-term bacteriological persistence but may improve adherence 1

Special Populations

Men with cystitis symptoms: 1

• Treat for 7 days (longer than women due to potential prostatic involvement) 1
• Trimethoprim-sulfamethoxazole 160/800 mg twice daily for 7 days 1
• Consider fluoroquinolones based on local susceptibility 1

Postmenopausal women: 1

• Same treatment as premenopausal women for acute episodes 1
• Consider vaginal estrogen for recurrent infection prevention 1

When NOT to Treat

Do not treat asymptomatic bacteriuria - presence of bacteria in urine without symptoms does not require antibiotics except in pregnancy or before invasive urinary procedures 1

Do not perform routine post-treatment cultures in asymptomatic patients 1

When to Obtain Urine Culture

Urine culture is recommended in these situations: 1

• Suspected pyelonephritis (fever, flank pain, systemic symptoms) 1
• Symptoms not resolving or recurring within 4 weeks after treatment 1
• Atypical symptoms 1
• Pregnancy 1
• Men with UTI symptoms 1

Treatment Failure Management

If symptoms do not resolve by end of treatment or recur within 2 weeks: 1

• Obtain urine culture and susceptibility testing 1
• Assume the organism is not susceptible to the original agent 1
• Retreat with a different agent for 7 days 1

Critical Pitfalls to Avoid

Fluoroquinolone overuse: These agents (ciprofloxacin, levofloxacin) are highly effective but should be reserved for complicated infections or pyelonephritis due to resistance concerns and adverse effects 1, 4, 2

β-lactam agents as first-line: Amoxicillin-clavulanate and oral cephalosporins are less effective than first-line agents for empirical therapy 2

Treating asymptomatic bacteriuria: This leads to unnecessary antibiotic exposure and resistance development without clinical benefit 1

Inadequate treatment duration: While shorter is better, single-dose antibiotics (except fosfomycin) have higher failure rates 1