What should you know about seafood anaphylaxis?

A reaction may follow eating seafood, touching it, or inhaling particles during preparation. Shellfish such as prawns, crab and lobster can trigger reactions, as can finned fish. Symptoms can develop quickly and may include widespread hives, swelling of the lips or tongue, throat tightness, wheezing, repeated vomiting, dizziness or collapse. A person can have anaphylaxis even without a skin rash; breathing or circulation symptoms are especially concerning.

A food allergy involves the immune system reacting to a food protein. Previous mild reactions do not reliably predict the next reaction, so a known seafood allergy should be taken seriously.

Use an adrenaline auto-injector immediately if one has been prescribed, following its instructions, and call emergency services. Tell the dispatcher that anaphylaxis is suspected. Lay the person flat with legs raised if possible; if breathing is difficult, allow them to sit with legs extended. Do not let them stand or walk. A second injector may be needed if symptoms do not improve and help has not arrived, according to the device instructions. Stay with the person and keep monitoring breathing.

After recovery, arrange allergy assessment to identify the trigger and make a written emergency plan. Ask about avoiding cross-contact in kitchens, restaurants and shared utensils.

Seek emergency help immediately for throat or tongue swelling, trouble breathing, wheezing, a hoarse voice, faintness, confusion, or sudden weakness after seafood exposure. Repeated vomiting together with skin or breathing symptoms is also urgent. Do not wait to see whether symptoms settle and do not drive yourself if a severe reaction is underway.

Ask which seafood needs to be avoided, whether an adrenaline injector is appropriate, how to use it, and how to recognise a reaction without skin symptoms. Discuss allergy testing and a plan for school, work, travel and eating out.