If you eat fish and then develop a blister-like rash that weeps and crusts over, you are most likely experiencing an allergic reaction to fish. Fish allergies affect an estimated 7 million people in the United States, according to the Food Allergy and Anaphylaxis Network. A common symptom of an allergy to fish is the development of eczema and other skin rashes after eating seafood. A fish allergy can also lead to a serious allergic reaction that could cause death.
A fish allergy occurs when your body identifies the proteins in fish as a dangerous substance. The immune system overreacts to the proteins and begins to defend the body by creating IgE antibodies that fight against the fish proteins. The IgE antibodies start a reaction in the body that causes various other chemicals to respond, causing allergy symptoms. Eczema can be the result of a fish allergy in some people. An allergy to fish is also linked to anaphylaxis, a severe life-threatening reaction that develops quickly: If you experience shortness of breath, dizziness, confusion, hives and a rapid heart rate, call 911.
Eczema is a chronic skin condition where the skin is hypersensitive to various triggers that can cause the rash to flare-up. As with many other allergies, the skin overreacts to certain substances that cause inflammation, swelling and itchiness, according to MedlinePlus. This skin condition is more common among children but can last a lifetime, affecting adults. Common triggers with eczema include extreme heat or cold, stress, airborne allergens and food allergies. If you're allergic to fish, you may experience an eczema outbreak after a few minutes of eating seafood.
Irritation in the skin causes eczema to flare-up. If you eat fish and have an allergic reaction, excessive amounts of histamine, a naturally occurring chemical in the body that helps fight off infection, are released in the skin, causing inflammation. Within a few minutes after consuming fish, you may notice spots developing around the mouth, on your face or elsewhere on your body. The spots will slowly develop into itchy bumps that will fill with liquid. Scratching the bumps will cause them to ooze and will leave the skin susceptible to infection. Talk with your doctor for an accurate diagnosis.
Treatment begins by eliminating fish from your diet, according to MayoClinic.com. Minor fish allergy symptoms may respond to over-the-counter antihistamines and may improve the eczema. Once eczema has developed, place a cold compress on the affected areas to alleviate the itch and swelling, according to MedlinePlus. You can also apply hydrocortisone creams to keep the rash under control. Avoid wearing tight-fitting clothing, and keep your skin moisturized.