Fish allergy symptoms explained

Medically reviewed on February 9, 2022 by Alyssa Clement and Jordan Stachel, M.S., RDN, CPT. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Fish is an excellent source of lean protein and omega-3 fatty acids, among other nutrients. However, studies suggest that about 2.3 percent of Americans are allergic to some form of seafood. Food allergies, in general, are serious health conditions that can lead to severe symptoms that can be potentially fatal. Fish allergies are no exception, and understanding the symptoms can help you stay prepared. Learn more about fish allergy symptoms below.

If you are experiencing an adverse reaction towards a specific food item, take the Everlywell at-home Food Sensitivity Comprehensive Test today to learn more about your IgG reactivity to foods (note: this is not an allergy test).

Symptoms of Fish Allergies

Much like other food allergies, a fish allergy comes from an improper immune response. This involves the immune system releasing antibodies known as immunoglobulin E (IgE). This antibody then releases the chemical histamine, which results in the physical symptoms characteristic of a food allergy [1].

Fish allergy symptoms can range from mild to severe, but the most common symptoms of an allergic reaction include:

• Hives, skin rash, or eczema
• Tingling or itching in the mouth
• Swelling in the lips, face, tongue, or throat that may also spread to other parts of the body
• Wheezing, congestion, and trouble breathing
• Digestive issues (abdominal cramping, diarrhea, vomiting, nausea)
• Dizziness or lightheadedness [1]

Severe allergic reactions result in anaphylaxis. Symptoms of anaphylaxis are serious and, left untreated, may lead to coma or even death. Serious fish allergy symptoms include:

• Tightening of airways
• Swelling in the throat that makes breathing difficult
• A sudden, significant drop in blood pressure resulting in shock
• Rapid pulse
• Fainting or loss of consciousness [1]

Allergic reactions typically occur within minutes of ingestion or exposure to an allergen. Some people may not develop allergic symptoms until a few hours [1].

Fish Allergens

The most common fish allergen is parvalbumin, a protein found in fish muscle tissue. As this protein is found in most fish, if you are allergic to one fish species, you’re probably allergic to others as well. Parvalbumin can maintain its allergenicity even after cooking, meaning cooked fish can still cause an allergic reaction. Furthermore, food products and processed foods containing fish, including sauces, soups, and garnishes, can trigger an allergic reaction [2].

As with other food allergies, reactions do not require ingestion of the food. Exposure to the allergen can trigger a reaction, either by breathing in airborne particles or making physical contact with the allergen.

Managing Fish Allergies

There is no known cure for food allergies, though some people are known to grow out of their allergies.

The best way to manage fish allergies is to avoid fish and any processed foods that may contain fish. Make sure that you read labels carefully to avoid fish, shellfish, or other seafood products, and know which foods commonly use fish, including salad dressings, Worcestershire sauce, and imitation crab. Omega-3 supplements made from fish oil may also trigger a reaction. When dining out, make sure you inform the server of your allergy to avoid any potential cross-contamination [3].

For mild reactions, antihistamines may help reduce symptoms, particularly symptoms affecting the skin, like hives and rash. For more severe reactions, you may have to use an epinephrine autoinjector and visit the hospital. Make sure you and those you live with know how to properly use the autoinjector and replace the injector once it hits the expiration date.

Fish allergies should be taken seriously. Understanding the symptoms that a fish allergy can cause may help you manage symptoms and take care of your health. If you want more information or think you may have a fish allergy but aren’t sure, consult your healthcare provider.

If you're wondering if you may be experiencing food sensitivities (which are not the same as food allergies), consider trying the at-home Food Sensitivity Comprehensive Test.

Suspect your uncomfortable symptoms like an itchy throat and sneezing may be due to environmental allergens? Check your immune response with Everlywell Indoor & Outdoor allergy tests.

Related content

What is the most common food allergy?

References

1. Food allergy. Mayo Clinic. URL. Accessed February 9, 2022.

1. Allergenic Foods and their Allergens - Fish. University of Nebraska-Lincoln Department of Food Science and Technology. URL. Accessed February 9, 2022.

1. Fish. American College of Allergy, Asthma, & Immunology. URL. Accessed February 9, 2022.