Understanding Puffer Fish Toxicity: Are They Really Poisonous?

The toxin in pufferfish is deadlier than cyanide. Still, some people consume pufferfish and swim alongside these creatures, putting their lives in danger.

Jun 5, 2024By Monika Dimitrovska
understanding puffer fish toxicity are they really poisonous

Pufferfish! They’re just as deadly as adorable.

In fact, they’re the second most poisonous vertebrate after the infamous golden poison frog, and the reason why they’re so poisonous is because they’re poor swimmers.

More interestingly, when pufferfish sense danger, they don’t run away; they gulp down lots of water (and sometimes air) and turn into a ballooned-up, unappetizing ball several times their original size.

Moreover, some of their internal organs contain a toxin that’s over 1,000 times stronger than cyanide. Let’s learn all the details!

Are Puffer Fish Poisonous to Touch?

puffer fish water
Image credit: Stelio Puccinelli from Unsplash

Pufferfish store their toxin, known as tetrodotoxin, in their liver, eyes, and sometimes skin; tetrodotoxin makes them taste foul and kill other fish.

The spines or sharp points covering their skin also contain the deadly toxin, so touching one is highly dangerous; even a small amount of the toxin can enter your body through small cuts or just through your skin and kill you.

They are one of the most venomous sea creatures in the world, and they live in different deep-sea zones as well as freshwater rivers.

Some people consume certain pufferfish, knowing that the toxin in one pufferfish is enough to unalive about 30 adult humans. The worst part? There’s no antidote! So, you wouldn’t want to eat a pufferfish unless you have a death wish.

puffer fish blue eyes
Image credit: Matt Bero from Unsplash

This delicacy in Japan is called fugu and costs a lot of money because it’s prepared by trained, licensed chefs. Regardless, many people still die after eating this dish.

When the toxin enters your body, it can cause paralysis and other serious health issues. In some cases, it can even be fatal if not treated right away.

To sum it up, you should stay away from puffer fish, even dead ones, because they can still contain the toxin.

The bad reputation of pufferfish is justified, unlike that of piranhas, which don’t actually harm people.

If you ever come into contact with a puffer fish or suspect you have, seek medical help immediately; don’t try to treat it yourself, as the toxin can be extremely dangerous.

Puffer Fish Poison Effects on Humans

white puffer fish spikes
Image credit: Kevin Yi from Pixabay

As we already stated, the toxin from pufferfish is called tetrodotoxin, and it can have serious effects on humans if consumed or even touched.

When people eat puffer fish that haven’t been prepared properly, the toxin can cause paralysis and even death. Tetrodotoxin actually affects the nervous system, making it hard or impossible to move, breathe, or speak.

If you eat a puffer fish with tetrodotoxin, you might feel sensations, weakness, dizziness, and eventually, get paralyzed.

Moreover, you might still be fully conscious but unable to move or breathe on your own. And without immediate medical treatment, you could die because your lungs collapse.

Even touching a pufferfish’s skin and spikes can result in paralysis or death.

Therefore, we don’t suggest eating or touching this deadly creature. Yes, consuming the popular dish might seem adventurous, but the risk of poisoning isn’t worth it.

Puffer Fish Poison Treatment

puffer fish
Image credit: Brian Yurasits from Unsplash

If you have come in contact with a pufferfish or suspect you have, you must ask for help immediately. Although there’s no antidote, doctors can provide treatments like breathing support and medicine to help counteract the effects of the toxin.

They might also flush out the stomach to remove any remaining poison.

In conclusion, you must get to the hospital as soon as possible, even if you start feeling better, because the effects of the toxin can be delayed and severe.

If you react quickly, you have a better chance of recovering safely.

Which Part of Puffer Fish is Not Poisonous?

puffer fish spikes
Image credit: Daniel Jiménez from Unsplash

Most parts of the pufferfish contain the deadly toxin. However, there’s one part that’s considered safe for consumption: the meat from certain carefully prepared species. The edible part is the white muscle tissue, which is mainly found in the fillets.

Still, this Japanese delicacy must be cooked by specially trained chefs who can remove all the poisonous parts (liver, ovaries, and skin) as they contain the highest amounts of tetrodotoxin.

They usually slice away any toxic organs and skin, leaving only the safe, edible meat. If cooked properly, puffer fish tastes delicate and feels smooth in your mouth.

Are Puffer Fish Safe to Swim With?

swimming with puffer fish
Image credit: James Lee from Unsplash

Absolutely not! It’s not safe to swim with pufferfish because of their poisonous skin and spikes. Moreover, if pufferfish feel threatened, they can become defensive and release their toxin as a defense mechanism.

They’re not the fastest marine animals nor the weirdest deep sea animals out there, but they’re definitely one of the most dangerous ones. That being said, we suggest admiring pufferfish from afar and avoiding direct contact with them while snorkeling or diving.


yellow puffer fish
Image credit: Stefanie Akkerman from Unsplash

Wrapping up, over 120 types of pufferfish live in warm oceans. They vary in looks and sizes and consume mostly invertebrates and algae.

Experts suggest that pufferfish get their poison from their food, and they even cover their eggs with it to keep them safe from predators.

While swimming with pufferfish or eating one might seem intriguing, we strongly advise against both practices because they’re as poisonous as they come.

Monika Dimitrovska
By Monika Dimitrovska

Monika is a pet enthusiast and seasoned copywriter with a tech degree. She loves writing, but her heart belongs to her two mixed dogs, Buba and Bono, a mother-son duo. Bono’s siblings found loving homes, sparking Monika’s advocacy for neutering and deepening her curiosity about animal care.

But Monika’s pet family doesn’t end there. She also has two cockatiels and two rescue cats, proving her home is a haven for creatures big and small.