After your doctor has diagnosed you with a urinary tract infection (UTI) the next task is to find out which bacteria has caused the infection. In ~80% of cases the troublemaker is E. coli, but there are about 45 recognized strains of that bacteria species and only about ten of those cause UTIs. Each strain responds in its own way to different antibiotics. Therefore, your doctor will have you do a urine sample test which will be sent to a lab for a urine culture.
This requires a couple of days of waiting for the urine culture to grow, be tested against different antibiotics, and the lab results to return to your doctor. However, it’s well worth the wait and you can use OTC painkillers like ibuprofen to ease the pain during the waiting period. Testing is the only method that can determine the bacteria strain with certainty and it allows your doctor to choose the antibiotic that will be most effective against it.
Due to decades of antibiotics treatment for UTIs, many E. coli strains already are resistant against the longest-standing antibiotics, such as ampicillin. Nowadays there are databases that doctors can check to see what bacteria strain is resistant to what medication. As doctors say, you need to match the “drug with the bug.”
So, when you first went to the doctor you probably expected to get a certain antibiotic. Something that you heard a friend say works well or even — if you previously had a UTI — an antibiotic you had been prescribed in the past. Well, as you now know, it doesn’t work this way. The bacteria strains that caused your friend’s UTI or your last UTI probably are different from the one behind your current UTI. Each UTI needs to be evaluated individually and requires customized antibiotic treatment, although in most cases it still comes down to Macrobid and Bactrim.
Aside from considering the bacteria, there are several other factors doctors have to weigh in order to decide which antibiotic to describe. This includes:
All of these are important factors to include when considering antibiotics prescriptions.
In the U.S. market, the FDA has approved several antibiotics for treating UTs and the most commonly prescribed are:
As you can see, there’s a wide range of antibiotic options and none of them are perfect or universally applicable to all UTIs. Therefore, it’s highly recommended that you talk to your doctor about doing a urine culture, even if it costs you more money and requires 2-3 days of painful waiting. Only such a test can help you find the right antibiotic treatment.