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 cancer cells 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).