Tetrodotoxin (TTX) is a very powerful nerve toxin found in the puffer fish and some other marine animals such as starfish.
TTX works by interfering with the ability of nerve membranes to transport sodium. Ingestion of small amounts of TTX produces a feeling of numbness in the face along with a floating sensation. Larger amounts can produce paralysis and death, although “large” is relative here, since less than a milligram can be fatal.
Puffer fish (or “fugu”) is considered a delicacy in Japan and even though only carefully trained chefs are allowed to prepare it, 179 deaths were reported in a ten year period due to eating fugu. Interestingly, TTX has been proposed by one anthropologist as an ingredient in the potions of voodoo practitioners in Haiti. The theory is that a victim is given TTX and slips into a paralytic coma indistinguishable from death, only to be revived later as the living dead, or a zombie! Fans of the Simpsons will remember that Homer once believed he was suffering from fugu poisoning.