I love the plant, Urtica dioica. It is known by many names . Some names are common nettles, stinging nettles, or greater nettle. These plants are weedy perennials and are common in North America, Europe Asia and even Africa. These plants are from the family Urticaceae. One of the courses I took at the New York Botanical Gardens after I finished my Botanical Medicine Program was Botanical Latin. In college I not only studied Latin, but was a teaching assistant for first and second year Latin students. The botanical Latin course at the NY Botanical Gardens (http://www.nybg.org) was great. The Latin word for nettle is urtica. The medical term for painful or intense hives is called Urticaria. The tiny fine hairs on some of the nettle plants deliver a sting. Thus, the name Stinging Nettles. These hairs are like fine hypodermic needle injections. Ouch!!!
Two compounds that are delivered with its sting are tartaric acid and oxalic acid. Both are irritating to the skin. These compounds are also found in some fruits and vegetables. There is a tiny amount of formic acid which is found in bee and ant venom.
I use the leaf of the plant for allergies and respiratory issues while I use the root of this plant for prostate disease
What I find odd is that the relief for the stings comes from the sap of the crushed leaves. In the United States we have it easy with the stinging nettles. One of the most potent nettle plants are the Tree Nettles from Australia and New Zealand. This plant also called Ongaonga, can cause blistering, a severe rash and intense stings. Animals that come in contact with this plant often die.