In laboratory studies, Pygeum africanum has been shown to inhibit prostate cell proliferation by reducing the response to a variety of growth factors. Pygeum africanum also is thought to produce anti-inflammatory effects and has been shown to improve bladder function in animal studies.
In Europe, a Pygeum africanum product called Tandenan is most commonly used. The usual dose is 100 mg per day.
There is limited research on the effectiveness of Pygeum africanum in men with symptomatic benign prostatic hyperplasia (BPH). As with most herbal therapies, most available studies on this bark are short term, and the supplements used are not standardized. In fact, when a review of the best quality studies using Tandenan (the European prescription product derived from Pygeum africanum) was attempted, no conclusions could be drawn because of inconsistency in the studies and results.
A few placebo-controlled studies from Europe, however, have demonstrated some positive effects.
In a six-week study involving 120 men, those who took Pygeum africanum had a greater improvement in several urinary symptoms than men who took a placebo.
Another study of 263 men over two months found that 66% of men taking Pygeum africanum felt that they improved, whereas 31% of men taking a placebo felt this way.
Still, Pygeum africanum remains unproven as a treatment for BPH.