UMEM Educational Pearls

Category: Toxicology

Title: "Food poisoning": How do you like your fish?

Keywords: ciguatera, scromboid, tetrodotoxin (PubMed Search)

Posted: 9/18/2014 by Hong Kim, MD
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Food poisoning can occur with many different food groups/items, as well as how the food is prepared, handled or stored.

There are three specific “food poisonings” associated with fish consumption can cause serious toxicity/illness beyond GI symptoms: Ciguatera, Scrombroid, tetrodotoxin (puffer fish)



  • Endemic to warm tropical water and bottom reef dwelling large carnivorous fish: grouper, red snapper, barracuda, amberjack, parrot fish, etc. (> 500 species).
  • Toxin: ciguatoxin: opens voltage gated Na channel
  • Produced by dinoflagellates (gambierdiscus toxicus) and bioaccumulates in large fish through food chain (eating small fish).


  • GI symptoms: n/v/d and abdominal pain
  • Hot/cold reversal
  • Paresthesia of tongue/lip >> extremities
  • Dental pain: “loose teeth”

May progress to develop…

  • T wave changes, bradycardia, hypotension
  • Respiratory paralysis and pulmonary edema

Treatment: supportive care and mannitol in presence of severe neurologic symptoms (limited evidence).



  • Endemic in (dark meat) fish living in temperate or tropical water: amberjack, skipjack, tuna, mackerel, albacore, mahi mahi, etc.
  • Associated with poor refrigeration/storage after catching fish.
  • Histidine in tissue is converted to histamine by bacteria on the fish skin.



  • GI symptoms: n/v/d and abdominal pain
  • Upper body flushing
  • Puritis, urticarial and perioral swelling can occur
  • Palpitation and mild hypotension


Tx: H1/H2 blockers and supportive care

Serious reactions: treat like allergic/anaphylactic reaction



  • Ingestion of improperly prepared puffer fish (fugu) sushi (or bite from blue ring octopus)
  • Toxin: tetrodotoxin: blocks voltage gated Na channel.
  • Highest concentration in liver and ovary.



  • GI: n/v/d
  • Progressive paresthesia and weakness (bulbar-> extremities), ataxia
  • Ascending paralysis and respiratory distress/paralysis
  • Dysrythmia and hypotension
  • Mental status preserved.


Treatment: supportive care and intubated if needed.