Tetrodotoxin (TTX) owes its name to the family of the pufferfish and was first isolated in 1950 from the ovaries of a pufferfish. Species of pufferfish such as Canthigaster valentini, Lagocephalus lagocephalus, Chelonodon patoca, Tetraodon fahaka as well as many species of the genus Fugu have been considered to be more toxic than other pufferfish species. The TTX is employed in the defence of pufferfish, in combination with their rather bizarre inflation behavior. The TTX containing eggs of pufferfish can also be highly toxic, probably to get protected from the predators. Saxitoxin (STX) has been detected in the skin, muscle, viscera, and gonads of Indian River Lagoon pufferfish. The toxic concentrations in pufferfish from the United States were also similar to those found in Philippine, Thailand, Japan, and South American countries. STX and its derivatives exert their neurotoxic effects by binding to membrane proteins in neurons and muscle cells.