tetrodotoksin

Tetrodotoxin (TTX), sometimes written tetrodotoksin in some languages, is a potent natural neurotoxin produced by certain marine bacteria and found in a variety of animals, most famously pufferfish (fugu). It is a small guanidinium alkaloid that can accumulate in tissues such as the liver, ovaries, and skin, and it is remarkably heat-stable, with cooking not reliably destroying it.

The primary mechanism of tetrodotoxin is the selective blockade of voltage-gated sodium channels on nerve and muscle membranes, preventing action potentials. This leads to rapid onset of neurological and motor symptoms. Exposure occurs mainly through ingestion of contaminated seafood or animals. Onset is typically 10 to 45 minutes after exposure, though it can be longer. Early signs include perioral numbness and tingling, followed by weakness, dizziness, ataxia, hypotension, and potentially respiratory failure. There is no widely available antidote.

Treatment is supportive and focused on airway, breathing, and circulation. Activated charcoal may be considered if ingestion was recent; some patients require mechanical ventilation for respiratory failure. Prognosis depends on dose and the speed of care, with recovery occurring as the toxin is cleared, which can take hours to days. Prevention relies on avoiding contaminated products and, in some regions, ensuring pufferfish are prepared only by licensed, trained chefs. Research continues into targeted therapies, but management remains primarily supportive.