Tetrodotoxin onset window after exposure typically falls within which time range?

• A. 10 minutes to 3 hours
• B. 30 minutes to 10 hours
• C. 1 hour to 2 days
• D. 5 to 20 minutes

Answer: (A)

Tetrodotoxin acts quickly after ingestion by blocking voltage-gated sodium channels, so nerve signals are halted soon after exposure. This produces rapid sensory changes and weakness that can progress to respiratory failure if not managed. Because symptoms tend to appear soon after ingestion, the typical onset window is about 10 minutes to 3 hours. A window like 5 to 20 minutes is narrower than most cases, while waiting until a day or longer is not consistent with the usual rapid onset seen with tetrodotoxin.