Fish allergies are separate from shellfish allergies, but having both is possible. A child who is diagnosed with a shellfish allergy will maintain the intolerance for life, AllergicChild.com states. When a fish or shellfish allergy is suspected, a skin prick test is done to expose the child or adult to a variety of fish, shellfish and mollusks. Based on the response to the test, a diagnosis can be made. Symptoms of shellfish allergy are similar to other types of food allergies.
Mild Symptoms
Allergic reactions can occur within a few minutes or hours after eating or being exposed to the shellfish. It is possible to have a reaction to foods fried in the same oil as shellfish. For example, signs of allergy can occur in an individual who eats french fries prepared in the same oil as shrimp. Mild symptoms of this type of allergy can include itching, hives, mouth tingling, throat itching or eczema. Individuals who have never experienced a food allergy before should monitor these mild skin reactions. More serious reactions to an allergen can occur shortly after the mild ones. Antihistamines, both oral and topical, can help relieve the skin conditions.
Breathing Difficulties
Airway constriction is one of the most serious types of allergic reactions. Consumption of shellfish can lead to chest tightness or shortness of breath. This is a serious reaction and requires medical attention. The individual may wheeze with each breath, develop nasal congestion or experience an asthma attack. Asthmatic individuals may have more frequent attacks when exposed to allergens. When breathing difficulties are accompanied by more serious systemic (full body) reactions, it may indicate anaphylaxis, the most serious sign of allergy.
Anaphylactic Reactions
The Food Allergy Initiative suggests shellfish to be one of the most frequent triggers of anaphylactic reactions. Anaphylaxis is a medical emergency that can lead to death. In addition to airway constriction, the blood circulation is interrupted, leading to several full-body reactions. Anaphylaxis can cause swelling of the lips, tongue or throat that leads to the obstruction of the airways. The individual may wheeze or gasp for air and may turn blue. A loss of consciousness can result. A sudden drop in blood pressure can cause the individual to feel faint or weak. The pulse rate can diminish or become rapid, suggests the Mayo Clinic. Anaphylactic shock describes the condition when the blood pressure drops dangerously low.
Any individual who has ever experienced anaphylaxis should wear a medical alert bracelet, card or necklace to alert others. A rapid treatment of adrenaline should be carried by the individual at all times for emergency situations. This treatment is not used in place of emergency medical care.
Digestive Symptoms
Some individuals may experience abdominal symptoms from the allergy. After consuming shellfish, the individual may develop abdominal cramping, pain, nausea, vomiting or diarrhea. Some individuals experience only mild digestive problems with no other signs of allergy.
