- Grayanotoxin
Grayanotoxin is a
toxin found inrhododendron s and other plants of the family "Ericaceae ". It can be found inhoney made from theirnectar and cause a very rare poisonous reaction called grayanotoxin poisoning, honey intoxication, or rhododendron poisoning. The toxin is also known as andromedotoxin, acetylandromedol, or rhodotoxin.Grayanotoxin is a polyhydroxylated cyclic diterpene. It binds to specific
sodium ion channel s incell membrane s, the receptor sites involved in activation and inactivation. The grayanotoxin prevents inactivation, leaving excitable cells depolarized. Empirically the toxin is C22H36O7.Gross physical symptoms occur after a dose-dependent latent period of minutes to three hours or so. Initial symptoms are excessive
salivation ,perspiration ,vomiting ,dizziness ,weakness andparesthesia in the extremities and around the mouth, low blood pressure andsinus bradycardia . In higher doses symptoms can include loss of coordination, severe and progressive muscular weakness,bradycardia (and, paradoxically,ventricular tachycardia ), and nodal rhythm orWolff-Parkinson-White syndrome . Despite the potential cardiac problems the condition is rarely fatal and generally lasts less than a day. Medical intervention is not often needed but sometimesatropine therapy,vasopressor s and other agents are used to mitigate symptoms.Honey from
Japan ,Brazil ,United States ,Nepal , andBritish Columbia is most likely to be contaminated with grayanotoxins, although very rarely to toxic levels. Historically the poisoning was associated with "Rhododendron luteum " and "Rhododendron ponticum " found around theBlack Sea . According to Pliny and laterStrabo the locals used the honey against the armies ofXenophon in 401 BCE and later againstPompey in 69 BCE.External links
Pliny the Elder on Mad Honey: [http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus%3Atext%3A1999.02.0137&query=head%3D%231358]
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