The most commonly prescribed medications for a urinary tract infection are short-course antibiotics, with treatment lasting as few as one dose or as long as seven days depending on the type of UTI and your overall health. For a straightforward, uncomplicated UTI, doctors typically choose from a small group of well-studied antibiotics that target the bacteria most often responsible.
First-Line Antibiotics for Uncomplicated UTIs
For women with a simple bladder infection, guidelines from the American Academy of Family Physicians recommend five first-line options:
- Nitrofurantoin (extended-release): 100 mg twice daily for five days
- Trimethoprim/sulfamethoxazole (TMP-SMX): one double-strength tablet twice daily for three days
- Trimethoprim alone: 200 mg twice daily for three days
- Fosfomycin: a single 3-gram dose, taken once
- Pivmecillinam: 400 mg three times daily for three days
All five are considered equally appropriate starting points. Your doctor will pick one based on local resistance patterns, your allergy history, and what you’ve taken recently. In areas where more than 20% of UTI-causing bacteria are resistant to TMP-SMX or trimethoprim, those two options are typically skipped in favor of nitrofurantoin or fosfomycin.
How Nitrofurantoin and Fosfomycin Work in Practice
Nitrofurantoin is one of the most frequently prescribed UTI antibiotics. The extended-release version is taken twice a day for five days. An older, immediate-release form exists too, dosed at 50 to 100 mg four times a day, but the extended-release capsule is more convenient and better tolerated. Taking it with food helps your body absorb it and reduces stomach upset.
Fosfomycin stands out because the entire treatment is a single dose. It comes as an orange-flavored powder that you dissolve in about half a cup of cool water and drink immediately. You never swallow the powder dry. Drinking extra fluids afterward helps flush the medication through your urinary tract. The simplicity of one dose makes fosfomycin appealing, though it can be more expensive than other options.
UTI Treatment for Men
Men get the same core antibiotics: trimethoprim, TMP-SMX, or nitrofurantoin. The key difference is duration. A randomized trial found that men need at least seven days of treatment for an uncomplicated UTI, compared to the three-to-five-day courses that work for most women. This longer course reflects the anatomy involved, since bacteria in men can be harder to fully clear from the urinary tract.
When Stronger Antibiotics Are Needed
Fluoroquinolones, a class that includes ciprofloxacin and levofloxacin, are reserved for complicated UTIs or situations where first-line drugs won’t work. The FDA has placed its strongest safety warning on fluoroquinolones, stating that the risks generally outweigh the benefits for uncomplicated UTIs when other options exist. Those risks include tendon damage, nerve problems, and mood changes that can sometimes be long-lasting.
For complicated UTIs, where the infection has spread to the kidneys or occurs alongside conditions like kidney stones or catheter use, doctors choose from fluoroquinolones, certain injectable antibiotics, or broader-spectrum options. The specific choice depends on how sick you are, whether you have risk factors for drug-resistant bacteria, and your own medical history.
UTIs During Pregnancy
Pregnant individuals are treated with a longer course of antibiotics, typically five to seven days, even for a simple bladder infection. The American College of Obstetricians and Gynecologists lists nitrofurantoin, certain penicillin-type antibiotics, sulfonamides, and fosfomycin as treatment options during pregnancy. However, the timing matters. Trimethoprim and TMP-SMX are avoided in the first trimester, and nitrofurantoin is best avoided in both the first and third trimesters due to potential risks to the baby. Your provider will choose based on which trimester you’re in and what the urine culture shows.
Pregnant women are also screened for bacteria in the urine even without symptoms, because untreated infections during pregnancy carry a higher risk of kidney infection and preterm birth.
Pain Relief While Antibiotics Work
Antibiotics start killing bacteria quickly, but the burning, urgency, and pelvic pressure of a UTI can linger for a day or two before you feel better. Phenazopyridine is a urinary pain reliever available both over the counter and by prescription. The typical dose is 200 mg three times a day. It numbs the lining of the urinary tract and can dramatically reduce that burning sensation within hours.
Phenazopyridine is strictly for short-term symptom relief, not a substitute for antibiotics. It turns your urine bright orange or red, which is harmless but can stain clothing and contact lenses. It should only be used for a couple of days while the antibiotic does its job.
Medications for Recurrent UTIs
If you get three or more UTIs in a year, or two within six months, your doctor may recommend a preventive antibiotic strategy. The American Urological Association outlines two main approaches.
Continuous low-dose prophylaxis involves taking a small daily dose of an antibiotic for months at a time. Common regimens include nitrofurantoin 50 to 100 mg daily, trimethoprim 100 mg daily, TMP-SMX at a reduced dose once daily or three times a week, or fosfomycin every 10 days. These doses are much lower than what you’d take for an active infection.
If your UTIs are closely tied to sexual activity, a different approach works well: taking a single low dose of an antibiotic right before or after intercourse. Options include TMP-SMX, nitrofurantoin 50 to 100 mg, or cephalexin 250 mg. This targeted approach uses less medication overall while still preventing infections at the most common trigger point.