Fish Allergy in Babies

Unlike some of the other top allergens, many people (up to 40%) with a fish allergy won’t develop a reaction until they are an adult (1). This doesn’t mean that fish allergy can’t happen in babies, but it’s important to keep it in the diet and watch for a reaction all throughout life.

Finned fish are different from shellfish. Being allergic to one doesn’t mean that you’ll be allergic to the other. In one study, salmon, tuna, catfish, and cod were the fish that seemed to cause the most reactions (1). Most people are told to avoid all types of finned fish if they are allergic to one type.

How to Introduce Fish

As with other allergens, introduce fish as the only new food that day. If you are looking for a more comprehensive guide to introducing allergens, check out my Allergy Introduction Handbook. Please note that some of these suggestions include other allergens (indicated with a *).

• Cooked, flaky fish
• Salmon burgers*
• Fish sticks*
• Tuna salad*

Diagnosis

The gold standard for the diagnosis of a food allergy is an oral challenge. While scary, it’s actually an easy test to perform: if the child eats the allergen, do they consistently produce a reaction? If so, they are allergic. Then, to confirm a diagnosis, a doctor may use a blood test or skin prick test. A medical professional should always make the diagnosis. A self-diagnosis can lead to unnecessary restriction.

How to Avoid Fish

It may not be as simple as just not eating fish. Fish can come into contact with other foods during processing. There can be cross-contact in the kitchen if the cook touches fish or fish product and then cooks another dish.

It’s very important to always check food labels. Companies need to list fish clearly on the ingredients list in plain language or under the label in a statement that reads “Contains fish.”

Places to Check

Always ask about ingredients in foods that you did not make yourself. When eating at a restaurant, there is always a risk of cross-contact, so it is important to make it very clear that there is an allergy.

You may want to completely avoid seafood restaurants. There is a high risk for cross-contact. You can also avoid fish markets and places where you would touch fish. Fish protein can be in the steam, so avoid places where fish is being cooked.

Types of Fish

This is definitely not an all inclusive list, but these are some of the common types of fish people are allergic to (or you can use to expose your baby to fish protein):

• Anchovies
• Bass
• Catfish
• Cod
• Flounder
• Grouper
• Haddock
• Hake
• Halibut
• Herring
• Mahi mahi
• Perch
• Pike
• Pollock
• Salmon
• Scrod
• Sole
• Snapper
• Swordfish
• Tilapia
• Trout
• Tuna

Unexpected Fish Sources

Definitely check labels, because all products are made differently, but fish can be in barbecue sauce, bouillabaisse, caesar salad dressing, imitation fish/shellfish, and worcestershire sauce.

Is iodine a concern?

Iodine is not what triggers an allergy in a fish allergy. Assuming you do not also have an iodine allergy, it is safe for you to use iodine or radiocontrast material.

Fish Allergy Symptoms

A reaction to fish can occur through the air if fish is being cooked and you breathe in the steam. Most reactions occur from eating fish or handling fish and then touching your eyes or mouth.

Although reactions can range from mild to severe, it is usually recommended for all kids with fish allergies to have an epi-pen with them at all times. Epinephrine is used to treat anaphylaxis, a severe reaction to allergies.

This is not intended as medical advice. If you have any concerns about your child, reach out to your physician. If your child is having multiple symptoms or severe symptoms, call 911.

	Mild	Severe
Skin	mild rash, some hives	widespread rash, hives all over the body
Face	itchy mouth, runny nose, sneezing	lip swelling, tongue swelling
Gastrointestinal	nausea	vomiting, diarrhea
Airway	none	coughing, wheezing, trouble breathing