CranberryKidney DiseaseSpinal Cord

Cranberry tablets prevent UTI in neurogenic bladder

Researchers from VA Boston Health Care System in West Roxbury, Massachusetts report that “cranberry extract tablets should be considered for the prevention of urinary tract infections (UTI) in spinal cord injured (SCI) patients with neurogenic bladder.”

A neurogenic bladder does not function properly due to nerve damage.

First, the details.

  • 47 patients with spinal cord injury and neurogenic bladder were randomly assigned to receive cranberry extract tablets or placebo for 6 months.
  • Then, they reversed treatment for an additional 6 months — crossover study.

And, the results.

  • There was a significant reduction in the likelihood of UTI and symptoms while taking cranberry tablets.
    • While taking cranberry tablets, 6 patients had 7 UTIs.
    • With placebo, 16 patients had 21 UTIs.
  • Patients with a glomerular filtration rate greater than 75 mL/min had the greatest benefit.
    • GFR is the rate at which blood is filtered into the kidneys. It’s the best indicator of how well the kidneys work.
    • A filtration rate of 75 mL/min means there is kidney damage, but just a slight decrease in function.

The bottom line?
Cranberry extract tablets were effective in reducing the risk of UTI in patients with spinal cord injury. In addition, the authors concluded, “Patients with a high glomerular filtration rate may receive the most benefit.”

The important difference from earlier studies is the use of cranberry extract tablets. The evidence for cranberry juice is mixed, with a negative review here, and a more positive review here. Proper patient selection also appears to be important.

11/2/08 19:53 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.