Compound Monograph
Histamine
A biogenic amine that acts as a signalling molecule in the body and is also the sting-causing irritant in nettle.
Classification
Histamine is a biogenic amine, part of the alkaloids class. Nitrogen-containing, often bitter and physiologically potent compounds — the group behind many of the strongest plant medicines and poisons.
Where Does It Come From? (3)
Histamine is a naturally occurring (and made in the body) biogenic amine, found in Nettle — stinging hairs, Many fermented and aged foods and 1 other source. It is flagged as moderately toxic.
Research & Evidence
Histamine is a biogenic amine produced from the amino acid histidine. In the body it is a key signalling molecule: it is released from mast cells and basophils during allergic reactions, acts as a neurotransmitter involved in wakefulness, and stimulates gastric acid secretion, acting through several receptor subtypes (H1 to H4). Antihistamine medicines work by blocking these receptors. Histamine is also found in plants and foods: it is one of the irritants in the stinging hairs of nettle, and it accumulates in many aged, fermented or spoiled foods.
Toxicity & Safety
Endogenous histamine is tightly regulated, but ingested histamine can cause problems. Scombroid poisoning results from eating fish in which bacteria have generated high histamine levels, producing flushing, headache, rash and gastrointestinal symptoms. Some people are sensitive to dietary histamine, and histamine release underlies allergic and anaphylactic reactions. Contact with nettle stinging hairs causes the familiar transient rash and itch.