If you suffer from a shellfish allergy, you're not alone. It's one of the most common allergies in the United States, affecting around 2.3 percent of the population, or 7 million people, according to the Food Allergy and Anaphylaxis Network. All seafood can cause a reaction, but shrimp, crab and lobster are the most common allergens. Around 60 percent of shellfish allergies develop in adults, and they usually last for life.
Symptoms
Symptoms usually develop minutes after you eat shellfish. They include hives, itching, eczema, stomach pain, diarrhea, nausea, and swelling of the lips, tongue, face or throat. You may experience wheezing, difficulty breathing or feel lightheaded and faint. For some, even a tiny amount of shellfish can cause a more serious or even life-threatening reaction, known as anaphylaxis. According to MayoClinic.com, your immune system releases a flood of chemicals that cause your body to go into shock. Your blood pressure drops suddenly, and your airways narrow, blocking normal breathing. You may have a rapid, weak pulse and skin rash, and may even lose consciousness. You need immediate treatment with epinephrine, and you should go directly to the emergency room.
Diagnosis
If you suspect you have a shellfish allergy, consult your doctor. You will usually be given a physical examination, and possibly skin or blood test. A skin test involves pricking the skin and exposing it to a small dose of proteins found in shellfish. If you're allergic, a rash will develop. A blood test involves sending a sample to a medical laboratory, where it will be screened for antibodies, your body's response to allergens.
Treatment
If you have a mild reaction, MayoClinic.com recommends an oral antihistamine. But if you experience a more severe reaction, it's essential to go to the emergency room immediately. Call 911 even if you don't feel very sick. If you are at risk, your doctor will prescribe epinephrine, such as an EpiPen, which you or another person can inject into your arm or leg. Make sure your family and friends are aware of this and know how to use it. If you stop breathing, somebody may need to perform cardiopulmonary resuscitation until paramedics arrive. Most people make a full recovery from anaphylaxis, but it's important for someone to stay with you for 24 hours to ensure you don't relapse.
Prevention
The only way to prevent a reaction is to completely avoid eating or handling shellfish. The Food and Drug Administration requires manufacturers to list common allergens, including shellfish, on food labels, but they do not have to list whether the food was produced in a facility that also handles seafood. When eating out, remember that even non-shellfish foods prepared in a seafood restaurant could contain shellfish, and the same oil could be used to fry different foods. Other foods such as fish stock, cuttlefish ink, artificial seafood and imitation shellfish could contain shellfish, according to the Cleveland Clinic. Always check labels and make sure you know what you are eating. In restaurants, ask staff detailed questions about how food was prepared.
