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One of the earliest accounts of mass poisoning dates back to the first century BCE when Roman troops were allegedly poisoned with honey by the Heptakometes of Turkey. The Roman soldiers were reported to be confused and vomiting and subsequently defeated in battle after eating the honey. We now believe that they were given honey made from the nectar of the flowering plant Rhododendron luteum.
Azaleas are very close relatives of rhododendrons and can cause the same type of toxicity. The toxic component of rhododendrons and azaleas can be found in very high concentrations in honey made by bees that feed on them. This usually occurs in dense populations of these plants, particularly in the Mediterranean region. In fact, the majority of more recent reports of poisoning from rhododendron and azaleas occurred in Turkey where people ingested the poisonous honey produced accidentally by small-scale beekeepers. There are also a few reports of toxicity in people who intentionally ate the honey because of a false belief that it could help with some ailments.
The poisonous honey is commonly referred to as "mad honey," a nickname earned because of the confusion it is known to cause. The toxin can cause very low blood pressure and heart rate as well as irregular heart rhythm. These symptoms could be life threatening.
Ingestion of the "mad honey" is not the only way people have been poisoned by azaleas and rhododendrons. Eating the leaves, nectar, or flowers of the plants can also lead to toxicity. Although rare, serious and life-threatening toxicity has occurred when people intentionally ate the plant. Similar to myths surrounding “mad honey,” there are some areas of the world where the plant is believed to have medicinal properties.
Poison Control is often called in the spring and early summer about children who put the flowers or leaves in their mouths or try to eat them, or when children mistake the flowers for honeysuckle and suck on the nectar of the azalea flower. Generally, only mild symptoms such as mouth irritation, nausea, and vomiting are expected from such cases. Still, it is important to keep a close eye on children and pets when they play outdoors to be sure they do not eat any flowers, leaves, fruits, or seeds. If azaleas or rhododendrons are kept indoors for decoration, be sure to keep them out of reach of children and pets. Finally, do not prepare food or tea from plants growing in the wild or in your yard.
Serkalem Mekonnen, RN, BSN, MPH
Certified Specialist in Poison Information
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