Puffer fish poisoning, or tetrodotoxication is an acute and potentially life threatening illness after eating puffer fish, or fugu. The mortality rate of this type of food poisoning is around 60%. Tetrodotoxin is a heat-stable toxin that is concentrated in the liver, intestines and ovaries of the fish. According to the Ishikawa health service association, tetrodotoxin is nearly 100 times more poisonous than potassium cyanide. Symptoms usually begin within an hour or so after ingesting the fish. Symptoms include lethargy, weakness, numbness of the face, lips and extremities, a floating sensation and emesis. These early symptoms are usually quickly followed by flacid paralysis and respiratory failure. Patients that survive require respiratory support and fully recover within 48 hours.