Updated

Parents frequently give their children cranberry juice as an alternative treatment for recurrent urinary tract infections (UTIs), but they rarely tell their pediatrician about it.

A new study shows that nearly one in three parents have given their children cranberry juice or other cranberry products to treat or prevent recurrent UTIs, but less than one in four told their pediatrician about this practice.

"It has become clear that parents frequently use cranberry for therapeutic purposes -- occasionally in lieu of standard therapy," says researcher Kathi Kemper, MD, a pediatrician at Brenner Children's Hospital, in a news release.

Cranberry products are widely used to prevent UTIs in adults and are considered generally safe.

But researchers say their results show that new studies are needed to determine the safety and effectiveness of using cranberry products to treat healthy children with recurrent urinary tract infections.

Read WebMD's "Detecting and Treating Urinary Tract Infections"

Clandestine Cranberry Use

Researchers say UTIs are the most common serious bacterial illness treated by pediatricians. In children who suffer from recurrent urinary tract infections, the long-term complications may include high blood pressure or kidney problems.

Many doctors recommend treatment with antibiotics to prevent recurrent UTIs in children at risk. However, researchers say it's hard to get kids to take all their medicine. Using antibiotics as a preventive measure can lead to antibiotic-resistant bacteria, which makes it more difficult to treat other illnesses. Many of the antibiotics used to treat resistant bacteria can cause kidney problems.

In the study, researchers surveyed 117 parents of children treated at a pediatric nephrology (kidney treatment) clinic about their use of cranberry products in treating recurrent urinary tract infections. Their children ranged in age from 6 months to 18 years.

The results showed that 74 percent of the parents had heard of using cranberry products to treat UTIs, and 29 percent had given them to their children. Most of the parents used cranberry juice and a few used cranberry pills or dried cranberries.

About half of those who had given cranberry products to their children used them to prevent or treat urinary tract infections. The other half cited a variety of other reasons for using cranberry therapies, such as "flushing out the kidneys" or when their child seemed to be having problems with urination.

Of the parents who used cranberry therapies on their children, less than one in four discussed it with their pediatrician.

Most parents had heard about using cranberry products for treating UTIs from the media, friends, or family, and 12 percent were advised by a health professional to try them.

The results of the study appear in the current issue of the journal Ambulatory Pediatrics.

Urine infections affect millions of people each year. They are treated with antibiotics that fight the most common cause of urine infection -- a bacteria called E. coli. Yet doctors may suggest treatments like cranberries, which parents can take on their own to prevent infections. Though cranberry juice is the form of cranberries most widely used, other cranberry products include cranberry powder in hard or soft gelatin capsules.

The way cranberries work to prevent urine infection is not completely understood. It is believed that cranberries prevent bacteria from sticking on the bladder wall, which inhibits their growth.

Read WebMD's "More Cranberries, Fewer Urine Infections"

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCES: Super, E. Ambulatory Pediatrics, July/August 2005; vol 5. News release, Wake Forest University Baptist Medical Center. National Center for Complementary and Alternative Medicine.