Why Does Seafood Make Some People Itch?

You may have heard people say “I can’t eat shrimp — it makes me itch!” It’s not just a weird myth — for many folks, seafood really can trigger that tingly, itchy feeling. Let’s break down why this happens, how you might avoid it, and what you should watch out for.

Why does seafood sometimes cause itchiness?

Here are the main reasons:

1. True allergy (immune reaction)
   For many, itchiness after seafood is a classic allergic response. Their immune system mistakes certain proteins in fish or shellfish as harmful, releasing histamine and other chemicals that cause itching, hives, swelling, etc. (more info at acaai.org)
2. “Pseudo-allergy” or histamine (scombroid) reaction Sometimes it’s not a true allergy at all. Instead, certain fish can build up histamine if they aren’t stored the right way — for example, if the fish isn’t kept cold enough after being caught. When fish like tuna, mackerel, or sardines sit in warm temperatures, naturally occurring bacteria on the fish start breaking down proteins and release histamine. Once that histamine builds up, cooking or freezing later won’t remove it. Eating that fish can then cause “scombroid poisoning,” which feels a lot like an allergic reaction — itching, flushing, rashes, or even stomach upset (more info at qld.gov)
3. Other causes, such as cross-contact or hidden protein, like traces of allergenic proteins that can transfer from one food to another (in restaurants or shared kitchens).

Tips to avoid allergy or itchiness

Here are some friendly, practical tips:

• Avoid the specific seafood(s) you’re allergic to — you don’t have to avoid all fish or shellfish necessarily.
• Always buy fresh seafood and make sure it’s handled properly (kept cold, not left out). This helps prevent histamine build-up.
• Cook seafood thoroughly (though cooking may not fix histamine issues, it helps reduce other risks).
• Do an allergy test with a qualified doctor (skin prick test, blood test) to know exactly which seafood you’re reacting to.
• If you have mild itchiness, your doctor may recommend antihistamines to relieve symptoms.
• Always have medical advice or emergency plan if your reactions have ever been severe.

More tips on seafood allergy:

baptisthealth.com

mayoclinic.org

Friendly advice

Don’t try to push through severe itchiness or swelling hoping it’ll go away. Be cautious, test, and work with your doctor. Also, don’t be embarrassed to politely ask for ingredient details when eating out — it’s smart, not rude.

Seafood can bring wonderful flavour — but for some people, it can also trigger itchiness or allergic symptoms. Be kind to your body: know your sensitivities, take precautions, and enjoy seafood only when it’s safe for you.

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