Initial Treatment for Uncomplicated Cystitis
For women with uncomplicated bacterial cystitis, prescribe nitrofurantoin 100 mg twice daily for 5 days as first-line therapy, or alternatively fosfomycin 3 g as a single dose, reserving trimethoprim-sulfamethoxazole only if local E. coli resistance rates are below 20%. 1
First-Line Antibiotic Options for Women
The 2024 European Association of Urology guidelines establish the following hierarchy for uncomplicated cystitis in women 1:
Preferred first-line agents:
- Nitrofurantoin macrocrystals 50-100 mg four times daily for 5 days, OR nitrofurantoin monohydrate/macrocrystals 100 mg twice daily for 5 days 1
- Fosfomycin trometamol 3 g single dose (though it has inferior efficacy compared to standard short-course regimens) 1
- Pivmecillinam 400 mg three times daily for 3-5 days (where available in Europe) 1
Second-line agents (alternatives):
- Trimethoprim-sulfamethoxazole 160/800 mg (one double-strength tablet) twice daily for 3 days—ONLY if local E. coli resistance rates do not exceed 20% 1
- Trimethoprim alone 200 mg twice daily for 5 days (equivalent to TMP-SMX in some regions) 1
- Cephalosporins (e.g., cefadroxil 500 mg twice daily for 3 days) if local E. coli resistance is <20% 1
Critical Resistance Considerations
The 20% resistance threshold for trimethoprim-sulfamethoxazole is based on expert consensus from clinical, in vitro, and mathematical modeling studies 1. This is a hard cutoff—if your local resistance exceeds 20%, do not use TMP-SMX empirically 1.
Fluoroquinolones (ciprofloxacin, levofloxacin, ofloxacin) are highly efficacious in 3-day regimens but should be reserved for more serious infections like pyelonephritis due to their propensity for collateral damage and resistance development 1. They are considered alternative agents for acute cystitis, not first-line 1.
What NOT to Use
Never prescribe amoxicillin or ampicillin for empirical treatment due to poor efficacy and very high worldwide resistance rates 1. β-lactam agents generally (including amoxicillin-clavulanate, cefdinir, cefaclor, cefpodoxime-proxetil) have inferior efficacy and more adverse effects compared to other UTI antimicrobials and should only be used when other recommended agents cannot be used 1.
Treatment for Men
For men with uncomplicated cystitis, prescribe trimethoprim-sulfamethoxazole 160/800 mg twice daily for 7 days (note the longer duration compared to women) 1. Fluoroquinolones can also be prescribed in accordance with local susceptibility testing 1.
Symptomatic Therapy Alternative
For women with mild to moderate symptoms, symptomatic therapy with ibuprofen may be considered as an alternative to antimicrobial treatment after discussing with the patient 1. However, immediate antimicrobial therapy is more effective than delayed treatment or symptom management with NSAIDs alone 2.
Diagnostic Approach
Diagnosis can be made clinically based on typical lower urinary tract symptoms (dysuria, frequency, urgency) and absence of vaginal discharge in women 1. Urine culture is NOT routinely needed for typical uncomplicated cystitis 1.
Obtain urine culture in these situations:
- Suspected acute pyelonephritis 1
- Symptoms that do not resolve or recur within 4 weeks after treatment completion 1
- Women presenting with atypical symptoms 1
- Pregnant women 1
Common Pitfalls to Avoid
Do not routinely order post-treatment urine cultures in asymptomatic patients—this leads to detection and unnecessary treatment of asymptomatic bacteriuria, contributing to antibiotic overuse and resistance 1, 3.
Do not prescribe 10-day courses when 3-5 day courses are appropriate—studies show shorter courses are equally effective with less collateral damage 1, 2.
Do not use fluoroquinolones as first-line therapy for simple cystitis—reserve these for pyelonephritis or complicated UTIs where they are truly needed 1.