Spanish fly is dangerous to use. The ingestion of Spanish fly can lead to a toxic overdose, with serious side effects ranging from severe abdominal pain and respiratory and heart problems to coma and even death.
Spanish fly is a substance derived from a beetle of the same name. These beetles are also known as blister beetles, since the poison they contain causes skin blisters to form in humans upon contact.
The principal irritant in Spanish fly, cantharidin, has a reputation for being an aphrodisiac because of the way it irritates the urethra on its way out of the body after digestion, causing men to develop an erection. Although historical examples of its use as an aphrodisiac exist, it is very dangerous to ingest Spanish fly in any quantity for any reason due to its toxic nature.
The ingestion of even small amounts of Spanish fly can lead to a toxic overdose, causing serious health problems and possibly death. In fact, rumors suggest that the Roman poet and philosopher Lucretius might have died from an overdose of Spanish fly. Ingestion of Spanish fly can lead to severe abdominal pain, renal failure and convulsions, among other ailments. Spanish fly is illegal in most countries due to its toxic nature.