Shellfish allergies are common in adults and can be severe, even life threatening. These food allergies can appear suddenly in adults who have had no evidence of food allergies in the past. Symptoms can be mild or severe and often increase in severity with each incidence. People who are allergic to one type of shellfish are often allergic to all forms of shellfish including shrimp, lobster, clams, oysters and all other shellfish.
Shellfish Allergies Vs. Food Poisoning
Often food poisoning or other ailments that happen in the hours after eating shellfish can be mistaken for an allergy. The severity of symptoms of an allergic reaction caused by exposure to shellfish varies from person to person and often become more severe with each exposure.
Symptoms of Shellfish Allergies
Symptoms are usually immediate, often beginning with a prickly sensation at the back of the throat as the food is swallowed. The prickle signals the beginning of a swelling in the throat that can cut off the air supply. This serious reaction is known as anaphylaxis and can be life threatening. Other less serious symptoms include a rash or hives, but could progress to more life threatening anaphylaxis with the very next exposure.
Other symptoms include hives, swelling of the face, tongue, throat or other parts of the body. Wheezing, congestion and trouble breathing can result, often quickly. Dizziness and loss of consciousness can follow.
Allergy Testing
Skin tests are available to confirm the presence of a shellfish allergy. A small amount of the suspected allergen is placed just under the skin. A red bump at the site of the prick indicates a positive allergic reaction.
Blood tests are also available that test the body’s response to shellfish. A RAST test or allergy screen can determine exactly which foods cause an allergic reaction.
Symptoms of Anaphylaxis
Anaphylaxis is a severe, life threatening reaction caused by an allergic reaction. Symptoms of anaphylaxis include a swelling in the throat that obstructs breathing, a sudden blood pressure drop, rapid pulse, dizziness, lightheadedness, shock or loss of consciousness. Symptoms occur within a few minutes of eating the food. Anaphylaxis is a medical emergency. If you suspect anaphylaxis, seek emergency medical care immediately.
Preventing Exposure to Shellfish
The only prevention for shellfish allergies is to avoid all contact with shellfish. Eating or handling shellfish can result in an allergic reaction. In a severely allergic person, breathing the steam from the cooking of shellfish or contact of the food with cooking oil that has been used to cook shellfish can cause a reaction. Care must be taken in restaurants that serve shellfish, making sure that an allergic person’s food does not come into contact with foods, oils or utensils that have been used to prepare shellfish.
It is possible to be exposed to shellfish in unexpected ways, and persons who have a shellfish allergy should carry an EpiPen at all times. When used immediately as the reaction begins, the EpiPen slows down the reaction and allows time for medical assistance.
For less severe reactions, antihistamines help relieve the allergic reaction.
Iodine Allergies
Iodine allergies are not the same as shellfish allergies, but people suffering shellfish allergies often also have iodine allergies. Most people with a shellfish allergy will have no problems with iodine, but it is important to be sure that medical personnel are aware of the possibility of allergies when medical tests involving iodine are done.
References:
CNN Health: Shellfish Allergy (Accessed March 10, 2010)
Women's Health Resource: Does Shellfish Allergy Mean Iodine Allergy Too? (Accessed March 10, 2010)
Diane Watkins - Diane is a writer and educator, an avid reader and researcher, a loving wife and the mother of 4 sons. Based in Tampa Bay, she enjoys ...
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