A bladder UTI (cystitis) is a bacterial infection that usually needs a short course of antibiotics. The best choice depends on local resistance and your history; a clinician typically prescribes one of the first-line agents below.
What guidelines recommend to try first. Tap one we rate for its independent monograph.
A first-line choice per the IDSA/ESCMID guideline — low resistance and effective for uncomplicated cystitis (not used if kidney infection is suspected).
Trimethoprim-sulfamethoxazole (TMP-SMX)
Appropriate first-line where local resistance among the bacteria causing cystitis is under about 20%.
Fosfomycin
A single-dose first-line option where available.
Fluoroquinolones (e.g. ciprofloxacin)
Effective but generally reserved (not first-line) because of side-effect and resistance concerns; used when first-line options aren't suitable.
General reference, not medical advice. Antibiotics are prescription-only; the right one depends on the specific infection, local resistance, your allergies, and your clinician’s judgment. Don’t self-treat, and never use leftover antibiotics or someone else’s — that drives resistance and can be dangerous. See a licensed clinician.