Urinary tract infecton (UTI) is a very common problem in young healthy women, afflicting approximately one-half of women by their late 20's. One of the most common antibiotics used to treat UTIs is Trimethoprim-Sulfamethoxazole (TMP-SMX), usually for total of three days. However, concerns about increased antibiotic resistance have led to increased interest in studying other antibiotics for UTI.

An alternative antibiotic which is also FDA approved for the treatment of UTIs is fosfomycin (Monurol). The effectiveness of fosfomycin in curing UTIs when given as a single dose is not well studied. The purpose of this research study is to determine what the cure rates are with a single dose of fosfomycin versus the more standard 3-day course of TMP-SMX.

Procedures subjects will undergo once they have read and signed the consent are:

Questions about their medical and sexual history and current symptoms of UTI. They will be asked to provide a urine and peri-urethral sample and then are randomly assigned to one of the two treatment groups.They will be given a sheet to record symptoms at home. They will be asked to return to the clinic in 5-8 and 28-30 days after completing antibiotic therapy.Follow-up questions will be asked and urine and peri-urethral will be self collected at each visit.

Inclusion Criteria:

• Non pregnant women in good health with symptoms of acute cystitis for less than 7 days

Exclusion Criteria:

• Pregnant, lactating, or not regularly contracepting
• History of chronic conditions such as diabetes
• Known anatomic abnormalities of the urinary tract
• Use of prophylactic antibiotics
• History of allergy or intolerance to any of the study drugs
• Recent (> 2 weeks)exposure to oral or parenteral antimicrobial
• History of UTI in previous 1 month

Participants who were dispensed the treatment intervention, completed some or all of the treatment intervention and were included in the summary of side effects.

30 days

All participants enrolled (N = 150 in each arm) were monitored for mortality or serious adverse events due to inherent processes in the campus health care system.

Other adverse events were collected at the 1st follow-up visit in participants who presented for this visit, and they were queried on each side effect.

The clinicians and participants were not blinded as to the assigned intervention.