Nettles

Scientific Name(S): Urtica dioica L. Family: Urticaceae

Common Name(S): Stinging nettle, nettle

Description: Nettle, or stinging nettle, is a perennial plant growing in temperate and tropical wasteland areas around the world. The plant has been naturalized in Brazil and other parts of South America. It grows 2 to 4 meters high and produces pointed leaves and white to yellowish flowers. Nettle has a well-known reputation for giving a savage sting when the skin touches the hairs and bristles on the leaves and stems. The genus name Urtica comes from the Latin verb urere, meaning 'to burn,' because of these stinging hairs. The species name dioica means 'two houses' because the plant usually contains either male or female flowers.

Uses of Nettles:

Prove as a diuretic, nettles are also being investigated as treatment for hay fever and irrigation of the urinary tract.

Extracts can be used to treat arthritis; it is also believed to be diuretic and uses treating hay fever are being investigated.

Nettle is used in hair shampoos to control dandruff, and is said to make hair more glossy, which is why some farmers include a handful of nettles with cattle feed.

Side Effects of Nettles:

Internal side effects are rare and are allergic in nature. External side effects result from skin contact and take the form of burning and stinging that persist for 12 hours or more.

Toxicology: Nettles are known primarily for their ability to induce topical irritation following contact with exposed skin. This contact urticaria is accompanied by a stinging sensation lasting 12 hours or longer. A report closely associates mast cells and dermal dendritic cells. Immediate reaction to nettle stings is caused by histamine content, while the persistence of the sting may be caused by other substances directly toxic to nerves.

The stinging hairs of the nettle plant comprise a fine capillary tube, a bladder-like base filled with the chemical irritant and a minute spherical tip, which breaks off on contact leaving a sharp-pointed tip that penetrates the skin. The irritants are forced into the skin as the hair bends and constricts the bladder at the base.

Summary: Nettles have been part of our culture for thousands of years. They are more widely recognized for their irritation, but have been found to have many pharmacological benefits, proving some "folk remedies" to be effective. Its use in bladder irrigation, BPH treatment, hay fever relief and its CNS depressant effects have all been studied. Other than contact urticaria, side effects with plant ingestion are rare. The young herb (before stinging cells form) can be consumed as a pot vegetable.