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How to manage Scombroid Poisoning

Cause

Scombroid poisoning follows eating contaminated fish of the scombroid family and includes mackerel, tuna, albacore, swordfish and bonito. The muscle of all these fish is rich in the amino acid histidine. Contamination due to improper preservation or canning allows bacteria entrance to the flesh of the fish. These bacteria break the histidine down to a poisonous amine called saurine, which has many of the properties of histamine.

Presentation

  •  The affected fish has a characteristic sharp, peppery taste and must be discarded immediately.
  •  A mixture of allergic-type reactions occurs following ingestion:
~ Migraine
~ Urticaria
~Asthma
~ Gut irritation
  • The victim develops an intense headache, with nausea and vomiting, an intensely itchy spreading rash, tightness of the chest with wheezing, palpitations, abdominal pain and diarrhoea; and circulatory shock can occur.
Prevention

The condition can be avoided by prompt freezing or eating the fish after catching it. Do not allow your mackerel or tuna catch to stand in the sun all day.

Treatment

  •  Induce vomiting as soon as possible unless the diver has already vomited or is very agitated by severe breathing difficulty. Emetics include ipecacuanha, drinking a glass of strong salt water or simply using a finger in the throat. Vomiting will reduce the amount of toxin absorbed.
  •  Obtain medical help urgently.
  •  Antihistamines must be given, preferably by injection.
  •  Acute breathing difficulties due to sudden severe asthma or sudden circulatory collapse and shock are medical emergencies. A doctor or emergency paramedic service must be summoned.
  •  If the diver is in a remote place with no recourse to any medical help: inject adrenaline 1:1 000 subcutaneously at a dose of 0.1 m/kg body mass, very slowly over five minutes. Draw back on the syringe before injecting to ensure that a blood vessel has not been entered by the needle. Do not inject adrenaline directly into a blood vessel! Automatic adrenaline injection kits are available (e.g. Epipen).
  •  Monitor the pulse continuously. It will become forceful and accelerate as the injection is given. If it rises above 120 beats per minute, stop injecting and wait until the pulse settles.
  • Watch the diver’s face. It will become extremely pale due to the vasoconstrictive effect of adrenaline.
  • Monitor respiration continuously. Be prepared for CPR.
  • Inject 2 000 mg of hydrocortisone intramuscularly into the upper outer quadrant of the buttock muscle.
  • Administer CPR if breathing and heart function fail.

TIP
Do not inject adrenalin directly into the bloodstream.

NOTE 
Adrenaline and hydrocortisone are emergency life-saving drugs and may only be considered when it is impossible to obtain any trained help. These medications are being given without expert opinion and offer only a hope of success in extreme circumstances.

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