Urtica urens is the botanical name for an annual herbaceous plant native to Europe and Asia and now naturalized in most of North America. It is related to the perennial common stinging nettle, but is much shorter and more compact. As such, it is known by various common names that distinguish it from its larger cousin, such as dwarf nettle, small nettle, and lesser nettle. What the plant comparatively lacks in stature it makes up for in stinging capacity since its leaves have a greater number of trichomes, or stinging hairs. This attribute may also mean that this species has more therapeutic value to offer since each needle-like injector stands ready to deliver a variety of pharmaceutical agents, namely serotonin, histamine, and acetylcholine.
While it may seem like this plant is something to be avoided, many people deliberately provoke it into surrendering its chemical compounds directly into their skin. All it takes to make this happen is to lightly press a finger to a hair tip, or simply brush against the leaf. This practice is known as urtication, or by the particularly colorful term, flogging with nettles. Contrary to popular belief, though, the plant doesn’t relinquish the entire stinger, only its tip.
The reward for engaging urtica urens in this manner is to actually counteract pain rather than produce it. In fact, many enthusiasts of natural medicine consider this an effective home herbal remedy for a variety of painful inflammatory disorders, such as arthritis and rheumatism. The mechanism behind this action is owing to the constituents found in the stinging hairs, all of which act as neurotransmitters to regulate signals between nerve cells and other cells. The end result produces temporary paraesthesia, a burning “pins and needle” sensation at the site of entry. Perhaps this is why this particular species is also known by the nicknames burn nettle and burn hazel.
There are several modes of administration for urtica urens. Topical formulations utilize the essential oil of the plant and are used to soothe various skin troubles, such as hives, rashes, and minor burns. Some encapsulated herbal remedies and liquid tinctures include nettle extracts for the treatment of gout, kidney stones, benign prostatic hyperplasia, and decreased milk production in nursing mothers. Urtica urens is also used in homeopathic medicine to treat many of the conditions listed above, as well as chickenpox and adverse reactions to eating shellfish. While the internal use of this herb is usually regarded as safe, allergic reactions may occur in some individuals.