Allergy to Fish

Finned fish allergy — to salmon, tuna, halibut, cod and others — commonly develops in adulthood and tends to be lifelong. A patient allergic to one species of fish often reacts to others, and fish protein can hide in dishes like Caesar dressing, Worcestershire sauce and imitation seafood.

Common symptoms

• Hives or skin rash
• Nausea, cramps, indigestion or vomiting
• Nasal congestion, sneezing or asthma symptoms
• Swelling or tingling of the lips and mouth
• Anaphylaxis in severe cases

Diagnosis & treatment

Testing determines whether the allergy applies to all fish or specific species. Management is avoidance — including cooking vapors and cross-contact at seafood counters — with an emergency plan for accidental exposure. Fish allergy is distinct from shellfish allergy; many fish-allergic patients tolerate shellfish, and testing can confirm this.