Am Fam Physician. 2005;72(11):2219
Clinical Question
What is the most appropriate duration of therapy for uncomplicated urinary tract infections (UTIs) in women?
Evidence-Based Answer
Three days of antibiotic therapy is as effective as longer courses for treatment of uncomplicated UTIs in women.
Practice Pointers
Uncomplicated UTIs in women are one of the most common indications for antibiotics. To prevent resistance, antibiotics should be used judiciously; thus, it is important to determine the minimum duration of antibiotic therapy required for treatment to be effective.
Milo and colleagues reviewed 32 randomized controlled trials (with a total of 9,605 patients) comparing three days of oral antibiotic therapy with longer courses for women 18 to 65 years of age. Pregnant women and women with symptoms that suggest upper UTI (e.g., fever, flank pain, vomiting, positive blood cultures) were excluded.
For short- and long-term resolution of symptoms, the reviewers found no difference between a three-day antibiotic course and a course lasting five to 10 days. Longer courses were more effective at clearing the bacteria on follow-up culture but also caused more adverse effects, and it is not clear that bacterial clearance results in improved patient-oriented outcomes. Although data were limited, organisms cultured were not more likely to be resistant to antibiotics after treatment in either group. For most women, a three-day course of antibiotics is sufficient to treat symptoms.
The Institute for Clinical Systems Improvement (ICSI) guideline1 recommends treatment with double-strength trimethoprim/sulfa-methoxazole (Bactrim DS, Septra DS), one tablet twice per day for three days; or trimethoprim (Proloprim) at a dosage of 100 mg twice per day for three days. For women who are allergic to these first-line medications, the ICSI guideline1 recommends ciprofloxacin (Cipro) at a dosage of 250 mg twice per day for three days, or nitrofurantoin (Macrobid) at a dosage of 100 mg twice per day for seven days. Telephone screening and prescription of treatment is appropriate if there are no complicating factors. In the office, urinalysis is adequate for evaluating symptoms.