Puffer fish is found in coastal areas of Indian Ocean and waters of South Pacific Ocean. Eating puffer fish can often cause food poisoning which can have high mortality rate. This sea fish is considered to be poisonous because of its potent venom called tetrodotoxin (TTX) that affects nervous system. There is no antidote yet found for the toxin.
In some parts of Asia especially Japan, puffer fish is considered to be a food delicacy. However, people may fall sick or collapse after consuming the fish if it is not cut and cooked correctly.Puffer fish is so called because of its inflatable nature. When it faces danger from predators the fish swallows huge amount of water and becomes like a huge ball many times bigger than its original size. The fish is also called by other names such as balloon fish, globefish, Patka fish, sugar toads, sea squab etc.
The venom tetrodotoxin present in puffer fish is more potent than cyanide. Immediate medical attention is critical from puffer fish poisoning. Since there is no specific antidote available treatment is symptomatic. The prognosis of patient may depend on the amount of toxin and how quick patient gets treatment.
What Causes Puffer Fish Poisoning?
Any person who eats puffer fish is at risk of suffering from puffer fish poisoning. Puffer fish contains toxin called tetrodotoxin (TTX). It is highly potent neurotoxin producing several serious symptoms and sometimes causing death of the person. This fish is found in oceans of tropical and subtropical region, mainly in Indian Ocean and South Pacific. The toxin is densely concentrated in the liver, ovaries, intestine and skin of the puffer fish. The body musculature does not contain the toxin.
Puffer fish poisoning is mainly seen in Japan because many Japanese regard and eat the fish as a food delicacy. During its reproductive period puffer fish is most toxic. Eating puffer fish can be deadly if it is not cut and prepared correctly. Poisoning occurs mainly after consuming wrongly prepared puffer fish dish.
Tetrodotoxin creates blockage and prevents proper supply of sodium to heart and skeletal muscles. It also prevents sodium infiltrate in the nervous system thus it causes serious electrolyte imbalance. The toxin also acts on medulla oblongata leading to respiratory distress.
Signs And Symptoms Of Puffer Fish Poisoning
People suffering from puffer fish poisoning develop symptoms within half hour to 5 hours after eating puffer fish dish. The severity and rapidity of symptoms depends on the amount of tetrodotoxin present in the eaten fish.
Following are the symptoms experienced after puffer fish poisoning:
- The initial symptoms include numbness and tingling sensation in lips and on the tongue. This is followed by numb feeling all over the face and in the extremities.
- Soon patient develops pain in abdomen, vomiting, nausea, diarrhea, and other gastrointestinal symptoms.
- Patient feels dizzy and intoxicated.
- Weakness in limbs, difficult or slurred speech, and breathing difficulty.
- Paralysis of limbs.
- Abnormal respiratory and heart rate.
- Severe toxicity may result in seizures and unconsciousness and coma.
Patient who survives from the acute symptoms for 24 hours usually recover without any disabilities and deficits. Death may occur due to paralysis of respiratory muscles.
How To Treat Puffer Fish Poisoning?
Till today researchers are not able to find any antidote for tetrodotoxin which is a potent poison found in puffer fish. Thus treatment is entirely supportive and symptomatic. The sooner the patient takes treatment lesser is the mortality risk. If puffer fish is consumed within few hours of developing symptoms, doctors may induce vomiting to flush out content from the stomach and prevent absorption of left over toxin.
Patient is given gastric lavage with activated charcoal which can bind with the toxin that is still not absorbed. Other vital parameters such as respiratory rate, pulse rate, blood pressure are constantly monitored and treated accordingly in ICU.
The first 24 hours after poisoning from puffer fish are critical. Usually if patient survives first 24 hours the prognosis is much better. Patient may survive without any residual deficits.