A soy allergy is considered by MayoClinic.com to be one of the most common food allergens in children. Soy is a legume, in the same family as beans, such as black beans, lentils and chickpeas. If you've been diagnosed with a soy allergy, you should be tested for other legume-related allergies, according to the Cleveland Clinic. A common symptom that develops within a few minutes after eating soy is a skin rash. Skin rashes can manifest in the form of eczema, hives or general itching. Talk with your doctor if you experience a rash after consuming soy.
Cause
A soy allergy is caused by a hypersensitivity of the immune system to the proteins found in soy, according to the MayoClinic.com. The immune system attempts to neutralize the allergen by producing antibodies to ward off the proteins. As the antibodies enter the blood stream, certain cells called "mast cells" begin to produce histamine to help the immune system fight off the soy proteins.
Effect
The chemical reactions that occur in the body during an allergic reaction cause inflammation. Inflammation in the lungs causes asthma, inflammation in the sinuses leads to nasal congestion, inflammation in the intestines leads to digestive issues and inflammation in the skin causes skin rashes to develop. Common symptoms of a soy allergy include shortness of breath, chest pain, wheezing, sinus pressure, postnasal drip, vomiting, diarrhea, stomach pain and nausea, according to the Cleveland Clinic.
Rash Consideration
The most common rashes associated with a soy allergy are eczema and hives. Eczema is an allergic skin rash that develops patches of leathery, dry skin and pimple-like blisters. The rash is primarily found on the back of the legs, the inlet of the arms and the face. The blisters can weep and crust over, leaving the skin vulnerable to secondary infections. Hives are welts that form in various shapes and sizes with defined borders. Hives are extremely itchy and can appear anywhere on the body.
Treatment
Treat rashes from a soy allergy with over-the-counter hydrocortisone cream or prescribed corticosteroid lotions. These steroid-based medications will reduce the inflammation and itchiness of the skin, according to the American Academy of Allergy, Asthma and Immunology. Take an oral antihistamine to treat mild soy allergy symptoms, such as nasal congestion, watery eyes and rashes.
Warning
Hives is one of the first signs of a severe allergic reaction to soy. If other symptoms develop, such as shortness of breathe, lightheadedness, a rapid but fain pulse and dizziness, call 911 for immediate medical attention.
