How do puffer fish kill?

Pufferfish kill primarily through the presence of tetrodotoxin, a potent neurotoxin found in their skin, organs, and sometimes in their flesh. This toxin blocks sodium channels in nerve cells, leading to paralysis and potentially fatal respiratory failure in predators or humans that consume the fish. Despite being highly toxic, some cultures prepare pufferfish as a delicacy, requiring skilled chefs to minimize the risks.