What is "lytta vesicatoria"

Blister \Blis"ter\, n. [OE.; akin to OD. bluyster, fr. the same root as blast, bladder, blow. See Blow to eject wind.]

1. A vesicle of the skin, containing watery matter or serum, whether occasioned by a burn or other injury, or by a vesicatory; a collection of serous fluid causing a bladderlike elevation of the cuticle.

   And painful blisters swelled my tender hands.
   --Grainger.

2. Any elevation made by the separation of the film or skin, as on plants; or by the swelling of the substance at the surface, as on steel.

3. A vesicatory; a plaster of Spanish flies, or other matter, applied to raise a blister.
   --Dunglison.

   Blister beetle, a beetle used to raise blisters, esp. the Lytta vesicatoria (or Cantharis vesicatoria), called Cantharis or Spanish fly by druggists. See Cantharis.

   Blister fly, a blister beetle.

   Blister plaster, a plaster designed to raise a blister; -- usually made of Spanish flies.

   Blister steel, crude steel formed from wrought iron by cementation; -- so called because of its blistered surface. Called also blistered steel.

   Blood blister. See under Blood.

Cantharis \Can"tha*ris\ (k[a^]n"th[.a]*r[i^]s), n.; pl. Cantharides (k[a^]n*th[a^]r"[i^]*d[=e]z). [L., a kind of beetle, esp. the Spanish fly, Gr. kanqari`s.] (Zo["o]l.) A beetle ( Lytta vesicatoria, syn. Cantharis vesicatoria), having an elongated cylindrical body of a brilliant green color, and a nauseous odor; the blister fly or blister beetle, of the apothecary; -- also called Spanish fly. Many other species of Lytta, used for the same purpose, take the same name. See Blister beetle, under Blister. The plural form in usually applied to the dried insects used in medicine.

Lytta vesicatoria or Spanish fly is an emerald-green beetle in the family Meloidae, with approximate dimensions of wide by long. The genus and species names derive from the Greek lytta for rage, and the vesica for blister. It is one of a number of species that are collectively called blister beetles; it and other such species were used in preparations offered by traditional apothecaries, often referred to as Spanish fly. L. vesicatoria is sometimes called Cantharis vesicatoria, although the genus Cantharis is in an unrelated family, Cantharidae.

The terms Spanish fly and cantharides are synonymous and are used, the latter in particular, to refer to dried insects of this species, and related preparations. Cantharides derives from the Greek kantharis for beetle, and eidos, meaning form or shape. Although formerly taken internally, for use as a diuretic, and for supposed aphrodisiac effects, and externally as a rubifacient, counterirritant, and vesicant, cantharide preparations are poisonous, taken internally at large doses, and can lead to human and animal fatalities. Poisoning by Spanish fly/cantharides is a significant veterinary issue; ingestion of beetles or their extracts—e.g., in infested hay or contaminated water—results periodically in serious toxic symptoms and the need for veterinary intervention, especially, in the U.S., in horses. Other specific cases of animal poisoning have been described: cattle in Africa with diarrhea and nephritis as a result of drinking contaminated water.

The perceived aphrodisiac properties of L. vesicatoria and its dried cantharides preparations are a result of its toxicology, specifically, irritant effects it has upon the body's genitourinary tract, although such views of this property are anachronistic alongside modern statements that the effect is painful and without pleasure. Moreover, seeking this outcome requires ingestion of the blister beetle preparation, and these, and preparations available illicitly in particular, can contain high concentrations of active agent that result in severe toxicity ( poisoning). Human poisoning consequences include oral, gastrointestinal (GI), rectal, and vaginal tissue irritation through to severe GI hemorrhaging and kidney dysfunction, organ failure, and death. Clinical and postmortem examination—e.g., by endoscopy and autopsy—reveal the destruction, as do laboratory findings of hematuria, proteinuria, and other reflections of the underlying pathologies. Management of cantharidin poisoning is only supportive.

Preparations from L. vesicatoria and other species have been the sources from which a pure natural compound (naturally derived chemical compound) called cantharidin has been isolated, which is largely responsible for the pharmacologic activities described. To add to confusion with nomenclature, the isolated molecule, cantharidin itself, is sometimes also referred to as "Spanish fly".