Putrefying fish may contain large quantities of histamine, formed by bacterial enzymes from histidine in the fish muscles. This form of food poisoning is one of the most common forms involving seafood. It was first recognized in scombroid fish but can affect nonscombroid fish as well.
Fish affected:
(1) scombroid: tuna, mackerel, bonito
(2) nonscombroid: sardines, bluefish, anchovies, mahimahi, salmon, herring, amberjack
The process is more likely to occur in raw, unfrozen fish. Toxic factors are heat stable and can persist after cooking, smoking, canning or freezing. Analysis of a food sample for histamine can confirm elevated levels.
Presentation:
(1) A "peppery" taste may be noted when eating the fish. Otherwise the fish looks and smells normal.
(2) Onset of symptoms is within minutes of eating the affected fish or may take up to 2 hours.
Symptoms:
(1) headache
(2) dizziness
(3) nausea and vomiting
(4) generalized erythema
(5) urticaria
(6) pruritis
(7) abdominal cramps and diarrhea
(8) heart palpitations
(9) burning and tingling around the mouth
(10) sweating
(11) in severe cases: bronchospasm and shock may occur
(12) may be misdiagnosed as acute coronary heart disease or a food allergy
Effects of medications:
(1) monoamine oxidase inhibitors may prolong or worsen an attack by inhibiting the breakdown of the histamine.
(2) antihistamines can reverse the syndrome: diphenhydramine, chloropheniramine, cimetidine
Effects of comorbid conditions
(1) Patients with asthma may develop life-threatening bronchospasm.
(2) Patients with heart disease may develop cardiac arrhythmias and/or shock.
