A shellfish allergy is one of the most common allergies, according to MayoClinic.com. Individuals may be allergic to one or two kinds of shellfish, or allergic to all types. Triggers can include all shellfish, such as clams, lobster, and shrimp, but octopus and squid can trigger the allergies as well. The allergy can be mild or severe, with a range of reactions.
Significance
According to the Food Allergy and Anaphylaxis Network, or FAAN, 2.3 percent of Americans, or over seven million people, have a seafood allergy. Shrimp, crab and lobster comprise most shellfish allergies, says FAAN, and shellfish allergies are typically lifelong.
Symptoms
Symptoms of shellfish allergies include hives; itching; swelling of the lips, tongue or face; wheezing or difficulty breathing; stomach pain or diarrhea; nausea; and lightheadedness and fainting. Some individuals have a tingling in the mouth as well. Anaphylaxis is a rare but serious allergic reaction that can occur, and treatment for this reaction includes a shot of epinephrine and treatment at the emergency department of a hospital. Anaphylaxis can present with a swollen throat or the feeling of a lump in the throat; difficulty breathing; shock; fast pulse; and dizziness or loss of consciousness.
Identification
Diagnosing a shellfish allergy involves not only a physical exam, but allergy testing that may include skin and blood tests. Even after an allergic reaction to shellfish, allergy testing is the only definitive way to diagnose the allergy, notes MayoClinic.com. Skin testing involves pricking the skin and exposing it to shellfish proteins; an allergic reaction will cause hives to form. Blood tests include an allergen-specific IgE antibody test, which may also be called a radioallergosorbent or RAST test, according to MayoClinic.com.
Treatment and Prevention
Avoiding shellfish completely is one way to avoid an allergic reaction. If an individual comes into contact with shellfish, she can treat the reaction with antihistamines if it is a minor reaction. If a severe reaction occurs, she should treat it as a medical emergency and seek care at a hospital. Individuals with a known shellfish allergy should carry an EpiPen at all times, which is a device that administers a shot of epinephrine. The shot can help keep the symptoms manageable during the time it takes to seek medical attention.
Considerations
According to the Cleveland Clinic, individuals with a shellfish allergy should be mindful of several things, including the fact that when shellfish is cooked, proteins may become airborne and can cause an allergic reaction. In restaurants, even non-shellfish foods may be cooked on a surface that was previously used to cook shellfish, which can also trigger allergies. Fried foods can trigger an allergic reaction if the same oil used to fry seafood is used to cook other foods, notes the Cleveland Clinic.
