stinging nettle (Urtica dioica), a plant that can form large colonies in orchards, farmyards, old pastures, ditches, and waste places. The stinging hairs on the undersides of leaves and the stalk can readily break, allowing chemicals such as acetylcholine, histamine, serotonin, moroidin, and leukotrienes to enter the skin via a painful sting. See also nettle. ▪ OBSERVATIONS: The sting from the needles is followed by swelling, accompanied by prolonged itching and numbness. ▪ INTERVENTIONS: The area exposed to stinging nettle should be irrigated with soap and water but not rubbed as this can release chemicals in needles remaining in the skin. Apply sticky tape to the area of exposure and then pull the tape away from the skin to remove needles. ▪ PATIENT CARE CONSIDERATIONS: Although itching can be intense, instruction should be provided not to scratch the area. Cool compresses and topical applications can promote comfort. Although there are medicinal benefits associated with the use of nettle, accidental exposure through the skin can be very uncomfortable.
