Nettle is a perennial herbaceous flowering plant native to Asia, Europe, and North America. The root is widely used to treat benign prostatic hypertrophy (BPH), allergies, arthritis, and inflammation. Nettle is usually combined with herbs such as saw palmetto and pygeum for the treatment of BPH. Several compounds have been isolated from nettle including flavonoid glycosides that appear to contribute to its biological effects, although the precise mechanism of action is unclear.

In vitro and animal studies indicate that nettle extract has reno- ⁽¹⁾ and hepatoprotective ⁽²⁾ properties, and is effective against colitis in mice ⁽³⁾. Other preclinical data suggest nettle has antiproliferative effects in prostate cancer cells ⁽¹⁰⁾, may protect against cisplatin-induced toxicity ⁽¹¹⁾, enhance cancer cell sensitivity to paclitaxel ⁽²²⁾ or increase cisplatin cytotoxicity ⁽²³⁾.

Studies in humans are limited, but suggest benefits with nettle in osteoarthritis of the hip, knee ⁽⁴⁾, and hand ⁽⁵⁾, gonarthritis ⁽²⁰⁾, and for symptoms associated with benign prostatic syndrome ^{(6) (7) (8)}. A combination of saw palmetto and nettle improved nocturnal voiding frequency compared to placebo, and was similar to tamsulosin or finasteride for moderate to severe lower urinary tract symptoms/BPH ⁽²¹⁾. In another study, nettle improved glycemic control in type-2 diabetic patients ⁽⁹⁾.