PURPOSE: Complementary and alternative medicine, including phytotherapeutic agents, or those derived from plant or herb extracts to treat symptoms, is widely accepted in the community. Men with bothersome lower urinary tract symptoms due to benign prostatic hyperplasia increasingly use such preparations. Phytotherapeutic agent quality is unregulated and in most instances the contents are unknown while erectile dysfunction and prostate cancer treatments have shown contamination with standard pharmaceuticals. Since trial results for benign prostatic hyperplasia phytotherapeutic agents are inconsistent, they may also be contaminated. Thus, we determined whether pharmacological doses of alpha-blockers and/or 5alpha-reductase inhibitors were present in a sample of phytotherapeutic agents for benign prostatic hyperplasia. MATERIALS AND METHODS: We analyzed 15 phytotherapeutic products marketed for benign prostatic hyperplasia. Only oral tablets or capsules were considered with teas, tonics and foods excluded from study. We made random purchases from shop front health stores and Internet retailers. All batches of commercial phytotherapy were analyzed by high performance liquid chromatography. Analysis was semiquantitative using extracts from alfuzosin, doxazosin, terazosin, tamsulosin, dutasteride and finasteride. RESULTS: In the 15 batches of different phytotherapeutic agents tested no interference secondary to contamination with alpha-blockers or 5alpha-reductase inhibitors was observed. CONCLUSIONS: All phytotherapeutic agents for benign prostatic hyperplasia in this study tested negative for alpha-blockers and 5alpha-reductase inhibitors. Inconsistent results in trials using phytotherapeutic agents are probably not explained by the presence of standard pharmaceuticals.