不良研究所

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Is "Spanish Fly" really an aphrodisiac?

"Spanish Fly" is a curious name for an extract of blister beetles since the beetles are not flies, nor are they Spanish.

The extract contains cantharidin,聽聽a substance that supposedly increases sexual desire.聽Not only does it not do that, it may eliminate all desire permanently.聽When ingested, cantharidin can kill.聽But when used in small doses topically, it can be an effective treatment for warts.聽

Some 1500 species of cantharidin-producing beetles can be found around the world. They do not bite or sting but can cause a great deal of physiological mischief if they are accidentally, or in some cases, purposefully ingested.聽Cantharidin is synthesized by the male beetle and is given as a nuptial gift to the female during copulation for the purpose of protecting her eggs.聽If a predator bites into a blister beetle egg, it learns to never do it again.聽Cantharidin causes terribly painful blisters.聽But that is not all it does.聽In humans, it can cause a burning sensation of the urinary tract that in men can provoke an erection.聽This effect is responsible for cantharidin鈥檚 undeserved historical reputation as an aphrodisiac that dates back all the way to ancient Roman times.聽 Augustus Caesar鈥檚 wife Livia supposedly slipped ground beetles into food to entice men into indiscretions for which they could be blackmailed.聽There are also accounts of Louis XIV鈥檚 lust for women being aided by cantharidin, but the most famous proponent of 鈥淪panish Fly鈥 as a sexual stimulant was the notorious Marquis de Sade who is said to have given prostitutes cantharidin-laced pastilles to 鈥渟et them on fire.鈥澛營t set them on fire alright, with burning abdominal pain.聽The Marquis and his valet were accused of poisoning the women and quickly fled to Italy.聽They were sentenced to death in absentia.聽 聽

Cantharidin also resulted in a death sentence for an American fisherman, but in a different fashion.聽In 1954, for some bizarre reason, the man came to believe that blister beetle extract would attract fish.聽He shook some ground-up dried beetles with water in a bottle, using his thumb as a stopper.聽Immediately after, in the process of handling his hooks, the fisherman pricked his thumb, and as most would do, proceeded to suck on it.聽There was enough residual cantharidin on the thumb to kill him.聽It doesn鈥檛 take much.聽The fatal dose of cantharidin is in the range of 10-65 milligrams.聽According to some accounts, blister beetle extract was one of the components in Giulia Tofana鈥檚 infamous 鈥渨idow-maker鈥 poison in the 17th century, although most evidence points to the poison actually being a mixture of arsenic, lead and belladonna.聽Whether Spanish Fly was a component of 鈥淎qua Tofana鈥 is contentious but there certainly was a belief that cantharidin was being used as a poison.聽Indeed, attempts were made to try to identify it in the bodies of victims who were thought to have been poisoned.聽A piece of an internal organ from the deceased would be extracted with oil and the solution placed on the shaved skin of a rabbit to see if blistering would be produced.聽聽聽

Pure cantharidin was first isolated by the French chemist Pierre Robiquet in 1810 who identified it as the substance being responsible for the blistering properties of the beetle eggs.聽The exact molecular structure was not proposed until the mid-twentieth century and was shown to be correct when the American chemist Gilbert Stork synthesized cantharidin from simple molecules.聽This was only of academic interest because there is no need to synthesize cantharidin commercially.聽Whatever amounts are needed for dermatological use or for animal husbandry can be extracted from beetles, which are not hard to find.聽Why in animal husbandry?聽In some cases, mating needs to be encouraged.聽As in humans, cantharidin can produce an erection in males prompting the animal to try to resolve the situation through mating.聽

Because of the myth of the aphrodisiac effect, various varieties of 鈥淪panish Fly鈥 are available for purchase on the web.聽It is unlikely they actually contain any cantharidin, which of course is a good thing given the danger of the actual compound. Mostly they are herbal concoctions based on cayenne pepper extract that will produce a mild burning sensation, mostly in the wallet.聽There are also some 鈥淪panish Fly鈥 candies available for purchase.聽You鈥檒l get some very ordinary candies wrapped in paper adorned with the name "Spanish Fly."聽聽In Germany, homeopathic remedies based on cantharidin are available for the treatment of urinary tract infections.聽They cannot cause any harm because homeopathic remedies are diluted to an extent where either none or a trivial amount of the original substance remains.聽Needless to say, such products cannot produce a physiological reaction and rely totally on the placebo effect.聽A 0.7% solution of cantharidin when applied to a wart, however, can produce a physiological effect.聽The compound can cause skin cells to disengage from each other resulting in the breakdown of a wart.聽Application must be done by a physician because the amount applied and the time the solution is left on the skin is critical.


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