Pygeum (herbal remedy)

Pygeum is a herbal remedy containing extracts from the bark of Prunus africana. It is used to alleviate some of the discomfort caused by inflammation in patients suffering from benign prostatic hyperplasia (enlarged prostate). Bark extract is marketed under the brand-names of Pigenil in Italy and Tadenan in France and used commonly in its natural forms in traditional African medicine.

The Natural Standard Research Collaboration states:

Contrary to what is stated by the N. S. R. C., WebMD states: "...Pygeum contains chemicals that help shrink the prostate to relieve urinary problems such as poor urine flow and nighttime urination in men with enlarged prostates."

The active ingredient of pygeum is considered to be n-docosanol.

Pygeum alters the activity of cytochrome p450, more specifically extremely strong inhibition of CYP3A4 and CYP2C9, suggesting that it may interfere with the effectiveness of other drugs or supplements.

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Wikipedia