UTI: Bactrim vs. Cipro

About two weeks ago, I developed a UTI and was put on a 3-day course of Bactrim, which seemed to have worked, judging by the disappearance of symptoms.

Yesterday, though, it became obvious to me that the UTI had returned (or I guess I could have developed a new one). I went back to the doctor and this time was put on a 5-day course of Cipro and my urine specimen was sent off to be cultured.

While Googling around for info on UTI pathogens, I found this, which concludes that E. Coli is the most common UTI pathogen and Cipro should be the drug of choice of UTIs. (The article appeared in the Central Africa Journal of Medicine. I have no idea if that’s relevant or not.)

Anyhoo, why would a doctor choose Bactrim over Cipro? The cost was about the same.

Well, assuming they both usually work to clear up UTI’s - there are two reasons:

  1. Fewer side effects - Bactrin is less likely to give you diarrhea or hives or you name it.

  2. Save Cipro for infections that are resistant to Bactrin - thus slowing the development of antibiotic resistance against Cipro.

That article is from 1997. There has been a tremendous increase in the number of fluoroquinolone (Cipro is in this class) prescriptions written in the last decade. And with it, of course, we’ve seen a concomitant rise in the resistance rates. Resistance rates are variable by geographic area. In general, with uncomplicated UTI in a female, in an area where Bactrim resistance is <20%, that should be the primary drug of choice. In cases like yours with recurrent infection, the urine should be cultured and a course of a different antibiotic should be considered. In some areas, Cipro resistance rates are as high or higher than those for Bactrim in which case, neither would be a good choice.

Here is an abstract from a more recent study.

Thank you, USCDiver. Just the kind of info I was looking for.

I’ve been jokingly telling people that I’m on Cipro, so bring on the anthrax! Has a real or perceived anthrax threat had anything to do with the increase in Cipro prescriptions and/or Cipro resistance? Some nut case sends an envelope full of talcum powder through the mail, and everyone who comes in contact with it is put on a prophylactic course of Cipro – that sort of thing.

To reinforce what USCDiver has said, an institution’s unique experience with the microbiological organisms that comes through its doors is more important than the literature, particularly outdated literature a continent away. One of the chief duties of infectious disease doctors at most hospitals is to not only see patients but provide an updated set of databases or tables to other physicians which describe the organisms and susceptibilities seen by that institution. So, the “correct” answer for a given infection may vary significantly between institutions, particularly geographically disparate institutions.

I think aside from the brief scare in 2001, there hasn’t been much talk of anthrax. The problem is that fluoroquinolones are unfortunately being commonly prescribed for problems that probably don’t need antibiotics at all, such as sinusitis which leads to increased incidence of resistance.

Bactrim would give me hives, Long Time First Time, but then again I have a known allergy to sulfa drugs.

I nearly got given some sort of sulfa eye drops once by an optometrist. Good thing he doublechecked with me about allergies before going to the back room for them. The thought of eye hivesshudder He was horrified, I was amused by the look on his face. No harm done.

As Cipro has become less expensive, it has become a more reasonable first-line choice, but the differences between Bactrim and Cipro functionally are trivial. Sulfa allergies are typically only a problem with longer term use–not with three days.

Here’s another article you might be interested in looking over: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1531733/

In general no one would really argue with either approach, in my opinion. I personally consider it 6 to 1, half a dozen the other. Knowledge of local sensitivity profiles might help, but uncomplicated cystitis in a young woman does not even mandate a culture.

Chief Pedant, as a kid I was put on 'em for about six months for recurring ear infections. One day I broke out in horrible hives. Long-term, yep. (And the ear infection problem still didn’t start calming down until past puberty. I still get them every couple of years or so. Such fun.)