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Related to grayanotoxin: Andromedotoxin


A neurotoxin found in the nectar of certain rhododendrons and related plants, such as some laurels of the genus Kalmia, and in unpasteurized honey produced from such nectar, and causing temporary effects such as nausea, vomiting, dizziness, and irregular heartbeat if ingested.

[New Latin (Leucothoē) grayāna, species name (after Asa Gray) + toxin.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
Rhododendron honey (mad honey), produced from the rhododendron genus growing in the Black Sea region, contains a toxic substance, grayanotoxin (Qiang et al, 2011; Gunduz et al., 2007; Koca &Koca, 2007; Jansen et al, 2012).
AbstractMad honey intoxication or grayanotoxin poisoning is caused by consumption of grayanotoxin-containing toxic honey produced from leaves and flowers of the Rhododendron family.
Poisoning in humans has been associated with the consumption of "mad honey", or honey containing grayanotoxin; Labrador tea; cigarettes; and various decoctions used in alternative medicine (JANSEN et al., 2012).
Mad honey poisoning occurs after people consume honey contaminated with grayanotoxin, a chemical contained in nectar from the Rhododendron species ponticum and luteum.
The cause of the poisoning is the toxin known as grayanotoxin found in honey obtained from the nectar of Rhododendron ponticum species growing naturally on the mountains in the region.
The cause of the intoxication is the grayanotoxin which has toxic effects on sodium channels (2) and induces increased parasympathetic tone that causes life-threatening bradycardia, hypotension, and altered mental status (3).
(5) Pompey's troops were led to the coast of the Black Sea, where they consumed honeycombs tainted with grayanotoxin, a toxin present in honey produced by bees gathering nectar from laurels and rhododendrons.
The drug has the effect of reducing blood pressure in animal experiments, due to the diterpenes it contains of the andromedan type (grayanotoxins).
pungens forests within the Great Smoky Mountains National Park, soaked in deionized water, and filtered to obtain extracts that probably included water-soluble grayanotoxins, a potential allelochemical common in members of the Ericaceae.
According to the article, this particular type of honey can contain substances called grayanotoxins, some of which may cause low blood pressure, slowed heart rate, vomiting, dizziness and other symptoms.
Add a little honey for sweetness, but beware the maddening aftermath -- if that honey is contaminated with compounds called grayanotoxins. Found in some rhododendrons, the toxins cause short-lived, rarely fatal symptoms that may mimic a heart attack, or dramatically affect the central nervous system.