Blister Beetle Poisoning in Horses




There is no antidote for cantharidin toxin. The success of treatment relies primarily on the speed of diagnosis, and the amount of cantharidin that was ingested.


Any horse that has been affected by cantharidin will be in need of intensive supportive therapy, including the administration of IV fluids to flush out the kidneys, rehydrate the animal, and return balance to the body’s electrolytes. Activated charcoal should also be administered in attempt to neutralize any toxin that is left in the gastrointestinal tract and mineral oil may be administered via a nasogastric tube to facilitate further rapid evacuation of the intestinal contents. Ulcer medication should be given, as well as broad-spectrum antibiotics, to prevent secondary bacterial infections.  Pain medication will also likely be given.  


Living and Management


Even when caught early, cantharidin toxicity has a guarded prognosis




The blister beetle congregates in swarms to feed on alfalfa fields during mating, which is normally in mid- to late summer.  Knowing where your hay is coming from along with close inspection of the hay this time of year in areas that harbor this insect are two ways to help prevent against this potentially lethal condition.