Antibiotics for urinary tract infections (UTIs)
|Generic Name||Brand Name|
|nitrofurantoin||Furadantin, Macrobid, Macrodantin|
|sulfamethoxazole with trimethoprim||Bactrim, Septra|
How It Works
These medicines kill the bacteria that commonly cause urinary tract infections (UTIs).
Most antibiotics come in pill or liquid form. Some may be given as a shot. The doctor may give this medicine in the vein (intravenously) if you have a severe kidney infection.
Why It Is Used
Antibiotics treat a UTI. And they prevent complications of infection such as kidney damage.
Antibiotics also prevent UTIs. The doctor might prescribe preventive antibiotic therapy for:
- Women who have recurrent UTIs (at least two UTIs in 6 months or three UTIs in 1 year).
- Pregnant women who had recurrent UTIs before getting pregnant or during pregnancy.
- People who have spinal cord injuries or other nervous system conditions that affect urination.
- People who have had a kidney transplant.
- People who are going to have surgery involving the urinary tract.
How Well It Works
Antibiotics are effective for most UTIs. With these medicines, you can expect relief of symptoms in 2 to 3 days.1
When taken as preventive therapy, antibiotics also reduce the number of recurrent UTIs. But studies show that this kind of treatment is short-acting. When you stop taking an antibiotic, you are likely to get another UTI.2
Common side effects of antibiotics are:
- Skin rash.
- Upset stomach.
Ciprofloxacin, nitrofurantoin, levofloxacin, and sulfamethoxazole with trimethoprim can cause you to be more sensitive to the sun. This can make it easier to get a sunburn.
- Avoid direct sunlight and sunlamps while you are taking this medicine and for 5 days after you have stopped taking it.
- Most sunscreens do not block enough of the ultraviolet rays to prevent a reaction to the sun (phototoxic reaction). If you cannot stay out of direct sunlight, cover as much of your body as you can with clothes.
Ciprofloxacin and levofloxacin increase the risk of a tendon rupture or other tendon damage. If you have sudden pain or swelling around your ankle, shoulder, elbow, or hand while you are taking one of these medicines, tell your doctor. Do not exercise until your doctor says it is okay.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Some of these medicines may not be safe to take during pregnancy. Make sure you tell your doctor if you are or could be pregnant.
Be sure to take all of the medicine your doctor gives you. Do this even if you feel better. If you do not take all of your medicine as prescribed, the infection may return. Not taking the full course of antibiotics also encourages the development of bacteria that are resistant to antibiotics. This makes antibiotics less effective. And it makes bacterial infections harder to treat.
Antibiotic resistance among bacteria that cause UTIs has increased steadily in recent decades. You and your doctor may have to try different antibiotics, and different combinations of antibiotics, to find the right medicine that will kill the bacteria that is causing your UTI. Before you start a new antibiotic, your doctor may use results of urine tests to help select a medicine.
Last Updated: June 8, 2009