This
poisoning is caused by
Tetrodotoxin(TTX), which is an extremely
potent neurotoxin present in the bodies of
fish in the
Tetraodontiformes and
fugu families - 1 mg of this
substance is enough to kill an
adult human. These fish have an
hereditary immunity to TTX and use it on their
prey. However, certain
pufferfish are considered
delicacies in Japan (as
sushi).
Chefs who wish to prepare
fugu sushi must be
licensed by the
government to do so.
Fugu poisoning has about a 50%
mortality rate.
The stages of tetraodon poisoning in humans
numbness (mouth) > loss of feeling in extremities > sense of floating > headache, nausea, etc (what coby said) > reeling > paralysis > respiratory distress > still conscious, possibly lucid, but completely paralyzed > death. This may take between 20 minutes and 8 hours.