Allergies occur when the immune system of a sensitive person overreacts to an irritating substance, or allergen. Itchiness, rashes and swelling usually occur when the skin is affected. The symptoms usually appear on the parts of the body that directly contacted the allergen, like the face and hands, but the puffiness and itchiness can spread if the allergy becomes severe.
If you are experiencing serious medical symptoms, seek emergency treatment immediately.
Swelling and Hives
People with food or drug allergies may experience hives and angioedema on exposure to allergy-causing substances. Hives are tiny, red bumps that appear on the surface of the skin, whereas angioedema is swelling of the deeper skin layers. A person with a food allergy may initially experience itchiness or swelling around the mouth upon eating the allergy-causing food. The mouth, throat, face and the entire body may swell or get puffy if the allergy worsens.
- People with food or drug allergies may experience hives and angioedema on exposure to allergy-causing substances.
Allergy to Cardboard
An allergic rash called eczema occurs in some people who have chronic skin allergies or a family history of allergies. The rash is very itchy and either dry and scaly or weepy and infected. In infants, the itchy rash appears around the cheeks, forehead and scalp. Older people may develop rash on the face, neck, elbows and knees. People who suffer from chronic eczema may experience intense, uncontrolled itchiness on random parts of the body.
- An allergic rash called eczema occurs in some people who have chronic skin allergies or a family history of allergies.
- People who suffer from chronic eczema may experience intense, uncontrolled itchiness on random parts of the body.
Contact dermatitis appears as an itchy, blistery rash where there was direct contact with irritating substances such as:
- rubber or latex
- hair products
The most commonly affected body parts are the face and hands. Contact allergy worsens when the skin is re-exposed to the irritant, and even a very small amount of the allergen can cause severe allergies 1.
Allergies That Cause Itching
Allergic rashes, swelling and hives can become very itchy, but scratching will only worsen the symptoms. Avoid rubbing or touching the affected areas. Instead, take an over-the-counter antihistamine and apply a topical hydrocortisone cream to relieve the itchiness and bring down the swelling. Swelling that occurs in the mouth, tongue and throat may make breathing difficult and become life threatening. If available, give a shot of autoinjector epinephrine and call 911 immediately to prevent symptoms from worsening.
- Allergic rashes, swelling and hives can become very itchy, but scratching will only worsen the symptoms.
- Instead, take an over-the-counter antihistamine and apply a topical hydrocortisone cream to relieve the itchiness and bring down the swelling.
Allergy to Cardboard
Allergies That Cause Itching
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Food Allergies That Produce a Rash on the Face
- AAAAI: Skin Allergy
- World Allergy Organization: Contact Dermatitis
- The American College of Allergy, Asthma, and Immunology. Skin Allergies.
- Eichenfield LF, Ahluwalia J, Waldman A, et al. Current guidelines for the evaluation and management of atopic dermatitis: A comparison of the Joint Task Force Practice Parameter and American Academy of Dermatology guidelines. J Allergy Clin Immunol. 2017;139(4S):S49-S57. doi:10.1016/j.jaci.2017.01.009
- Smith AR, Knaysi G, Wilson JM, Wisniewski JA. The Skin as a Route of Allergen Exposure: Part I. Immune Components and Mechanisms. Curr Allergy Asthma Rep. 2017;17(1):6. doi:10.1007/s11882-017-0674-5
- Bernstein JA, Lang DM, Khan DA, et al. The diagnosis and management of acute and chronic urticaria: 2014 update. J Allergy Clin Immunol. 2014;133(5):1270-7. doi:10.1016/j.jaci.2014.02.036
- Siegfried EC, Hebert AA. Diagnosis of Atopic Dermatitis: Mimics, Overlaps, and Complications. J Clin Med. 2015;4(5):884-917. doi:10.3390/jcm4050884
- Fonacier L, Bernstein DI, Pacheco K, et al; American Academy of Allergy, Asthma & Immunology; American College of Allergy, Asthma & Immunology; Joint Council of Allergy, Asthma & Immunology. Contact dermatitis: a practice parameter-update 2015. J Allergy Clin Immunol Pract. 2015;3(3 Suppl):S1-39. doi:10.1016/j.jaip.2015.02.009
- Tilles SA. Allergic Skin Disease and the Practicing Allergist: Growing Unmet Need, New Science, and New Treatments. Immunol Allergy Clin North Am. 2017;37(1):xiii-xiv. doi:10.1016/j.iac.2016.10.002
Grace Ibay has been a freelance writer and blogger since 2005, specializing in the medical sciences and health care. She worked at Johns Hopkins University and the National Institutes of Health as a research associate and has been published in various scientific journals. Ibay holds a master's degree in health science from Johns Hopkins University in Maryland.