There is more to it than the sting

Stinging nettle (Urtica dioica) is one plant you learn about quickly when you walk into it. The serrated leaves and stems are covered with stinging hairs that contain histamine, serotonin, and acetylcholine. When the stinging hairs are touched, they can cause local irritation and a burning sensation that may last for several hours. Fortunately, the stinging hairs on the plant are inactivated by drying or cooking the plant.
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