If you’ve recently changed your diet and you notice a neck rash, discontinue the diet and call your doctor. Neck rashes are a common symptom of a food allergy that results in dermatitis herpetiformis or hives -- an allergic skin rash that may develop within a few minutes after eating a food that triggers an allergic reaction. Although a neck rash is typically not a sign of a more serious condition, hives can be an indication of a severe allergic reaction.
Food Allergies
Most food allergies are found in children under the age of four and subside by adulthood. Food allergies that do not go away with age include shellfish, peanuts and tree nuts. The Asthma and Allergy Foundation of American states that about one to two percent of adults in the United States suffer from food allergies. The most common foods that trigger an allergic reaction include eggs, milk, soy, wheat, fish, tree nuts and peanuts. You can develop a food allergy to any food, especially if it’s the first time eating it. Most food allergy symptoms are mild, but in rare cases you may develop a severe allergic reaction that could lead to death.
Cause
Your immune system helps protect the body. Cells from the immune system in your bloodstream identify potentially harmful substances and attempt to rid them from the body. When the immune system malfunctions and reacts to a substance that is otherwise considered safe as if it were harmful, you experience an allergic reaction. Immunoglobulin E antibodies target the proteins from the food, which causes mast cells to create histamine in soft tissues. Histamine results in inflammation in different parts of the body, such as the digestive system, respiratory system and your skin.
Dermatitis Herpetiformis
Dermatitis herpetiformis is a chronic skin condition that causes extremely itchy blisters and bumps that may appear as scratches instead of blisters. The exact cause of this skin condition is unknown, but is commonly associated with gluten sensitivity. Gluten is a protein found primarily in wheat, rye, oats and barely. If diagnosed with this condition, you will need implement a strict gluten-free diet and may need a prescription for an antibiotic, according to MedlinePlus.
Hives
Hives can form anywhere on your body and cause extreme itching and inflammation. Most hives develop in clusters and appear as flat-surfaced welts and can from within minutes of consuming a food that triggers an allergic reaction. Each welt is red in color and has defined borders that can join together to form larger welts. The more you scratch hives, the more the rash will spread throughout your body.
Concerns
If you develop shortness of breath and swelling in your throat, face, lips or tongue, along with a neck rash, you may be experiencing anaphylaxis. Anaphylaxis is a severe reaction that can lead to death if not treated with an injection of epinephrine. Call 911 immediately if you develop these signs.
