Forskolin, a common herbal extract available in health food stores, has been found to reduce urinary-tract infections and potentially enhance the ability of antibiotics to kill bacteria that cause 90 percent of infections in the bladder.

In a series of experiments with mice, researchers at Duke University Medical Center discovered why many urinary-tract infections in the bladder return after treatment with antibiotics. They found that some bacteria hide in cells lining the bladder, where they cannot be reached by antibiotics. However, they also found that forskolin, an extract from the Indian coleus plant, forces out hiding colonies of bacteria into the urine, making them susceptible to antibiotic treatment.

About 90 percent of urinary tract infections in the

bladder are caused by E. coli bacteria. These infections afflict women four times as often as men and, in a large number of cases, the infection returns within weeks of antibiotic treatment.

The research was led by Duke microbiologist Soman Abraham, PhD, who published the results in the journal Nature Medicine. He said the herb, which is known to rev up certain cellular activity, has been used in Asia for centuries for treating painful urination.

Herbal extracts such as forskalin are not tested nor regulated by the Food and Drug Administration. Abraham recommends that anyone with a urinary tract infection contact their physician before trying forskalin.