PC-SPES is a mixture of 8 herbs that was sold as a dietary supplement to keep the prostate healthy (see Question 1).
Some batches of PC-SPES were found to contain prescription medicines. It was taken off the market and is no longer being made (see Question 1).
Herbs in PC-SPES have been used in traditional Chinese medicine for many health problems, including prostate problems, for hundreds of years (see Question 2).
The herbs used in PC-SPES have been reported to help keep cancercells from growing or help prevent cell damage that can lead to cancer (see Question 3).
Laboratory and animal studies suggested that PC-SPES might slow the growth of prostate cancer cells, but it is not known if these results were caused by the herbs in PC-SPES, prescription medicines that were found in the mixture, or both (see Question 5).
Clinical trials suggested that PC-SPES lowers PSA (prostate specific antigen) and testosterone levels in humans and has some anticancer effects. It is not known if these results were caused by the herbs in PC-SPES, prescription medicines that were found in the mixture, or both (see Question 6).
The U.S. Food and Drug Administration has not approved PC-SPES for use in cancer treatment (see Question 8).