A skin rash that comes on after handling or eating shellfish may indicate a serious food allergy. If you don’t suspect other known triggers for contact dermatitis, a group of allergy symptoms that affect the skin, you should consider being tested for shellfish allergies. Echinoderms such as sea urchins, mollusks such as oysters and crustaceans such as shrimp may cause allergic reactions. Among shellfish, however, the crustaceans shrimp, lobster and crab generate the most allergic illness in Americans, according to the Food Allergy and Anaphylaxis Network, or FAAN.
The symptoms of allergic contact dermatitis include skin irritation and redness, warmth and itching. Patches of skin may erupt in hives, or raised bumps, or may form fluid-filled blisters. The University of Maryland Medical Center relates that these allergy symptoms can appear immediately after touching shellfish or up to two days later. Shellfish allergies occur in both adults and children.
If your allergy symptoms are limited to the skin you may still experience a wider range of health problems at any time. FAAN reports that handling and cooking shellfish enables its protein allergens to become airborne and inhaled, which can intensify your body’s response. Additional health effects include runny and stuffy nose, mouth itching and swelling, digestive upset and rare episodes of anaphylaxis, a full-body allergic reaction.
If you have shellfish allergies, any contact with the microscopic allergens can initiate anaphylaxis, although the condition occurs less often from skin contact than from inhalation or ingestion. The National Institutes of Health advises an immediate call to 9-1-1 if you develop additional allergy symptoms of abnormal pulse, weakness or trouble breathing. Anaphylaxis can swiftly escalate to loss of consciousness, respiratory arrest, coma and death.
While allergies in children can come and go, shellfish allergies usually remain for life, the National Institute of Health reports. Permanent food allergies can’t be cured or even alleviated with immunotherapy shots, placing patients with shellfish sensitivities at continual risk for serious anaphylactic allergic reactions.
You may get skin rashes from substances unrelated to shellfish, such as other foods or household cleansers. Seeing a doctor for a diagnosis can identify a potentially serious problem with shellfish or rule out an allergic reaction. The National Institutes of Health notes that a skin test, blood test or special diet may reveal the need for you to remove shellfish and other fish from your menu in order to stay healthy.
Although the rash will begin to fade when shellfish contact ceases and allergens pass from your body, stubborn rashes can linger. The UM Medical Center recommends topical medications and creams to ease skin irritation. Commercial preparations of corticosteroid cream and calamine lotion will treat inflammation and itching.