The Archives of Internal Medicine just published a study Cranberries vs Antibiotics to Prevent Urinary Tract Infections A Randomized Double-blind Non inferiority Trial in Premenopausal Women and the findings were in favour of antibiotics over cranberries for preventing UTI's. Not all is lost though and I think cranberries can be part of a whole treatment plan.
- 221 premenopausal women with recurrent UTI's were randomly assigned to either trimethoprim-sulfamethoxazole (TMP-SMX), 480 mg once daily, or cranberry capsules, 500 mg twice daily
- the median number of urinary tract infections during the year before enrollment was seven.
- the mean # of patients with at least 1 symptomatic UTI was 4.0 in the cranberry group and 1.8 in the antibiotics group
- The proportion of patients with at least 1 symptomatic UTI was 71.1% in the cranberry group and 78.2% in the antibiotic group
- The median time to the 1st symptomatic UTI was 4 mths for the cranberry group and 8 mths for the antibiotic group
Antibiotic group
- 86.3% of fecal and 90.5% of asymptomatic bacteriuria E coli isolates were TMP-SMX resistant
- increased resistance rates for trimethoprim, amoxicillin, and ciprofloxacin in these E coli isolates after 1 month
- After discontinuation of TMP-SMX, resistance reached baseline levels after 3 months.
- TMP-SMX is 90% bio-available
Cranberry group
- Antibiotic resistance did not increase in the cranberry group
- The dose of proanthocyanidins was 9.1mg/g which is low according to newer research that suggests a dosage of 72mg a day
- Bioavailability of proanthocyanidin compounds is less than 10%
There is a lot of good news here for cranberry. The dosage given does not seem to be adequate. What would have happened if the dosage would have been much higher? Cranberry was almost as effective as antibiotics as shown by the proportion of patients with at least 1 symptomatic UTI (71.1% in the cranberry group versus 78.2% in the antibiotic group). The antibiotic group had much higher antibiotic resistance and increased resistance rates for other antibiotics.
As part of a total treatment that included other supplements that have shown benefit in preventing UTI's such as probiotics and vitamin C the outcome could be quite different. A typical treatment plan could include dietary recommendations and herbs, among other things.
Sabra
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