3 Common Skin Allergy Rashes & How to Identify Them

Various conditions affecting the skin can cause itchiness and rashes, but only some are related to an allergy. There are many types of skin allergies and rashes that can cause itchiness and inflammation.

However, not all rashes that itch are related to skin allergies. Insect bites and autoimmune conditions, along with fungal, bacterial, and viral infections, can all cause an itchy rash. 

While there may be other reasons for your rash, allergic reactions are still among the most common causes of skin rashes.

A woman with a patch on eczema on her neck
-aniaostudio- / Getty Images

This article reviews the most common skin rashes and shows pictures of each.

Atopic Dermatitis (Eczema)

Atopic dermatitis, more commonly known as eczema, frequently occurs in young children, although it may start in young adults, and can continue into adult life. This rash occurs where a person scratches.

In infancy, the rash most often occurs on the cheeks and/or scalp. Older children and adults typically have the rash in the skin folds of the elbows and behind the knees, although it may also occur on the ​face, neck, hands, feet, and back.

The rash is red, often flakes or oozes, and has small blisters or bumps. There are often excoriations, or areas of broken skin, from aggressive scratching. In cases where eczema does not improve with emollient (moisturizer) use alone, a thorough evaluation by an allergist-immunologist is warranted. Prescription creams and ointments or systemic medications may be required to control severe eczema. In rare cases allergic triggers (including contact allergens and environmental exposures) may also be identified that upon removing may significantly improve rash.

Atopic Dermatitis_hands_Courtesy_of_DermNet_NZ_scorad1__WatermarkedWyJXYXRlcm1hcmtlZCJd
Courtesy of DermNet NZ

Urticaria (Hives) and Angioedema (Swelling)

Urticaria, commonly referred to as hives, is an itchy rash that can occur at any age. This rash appears as raised red bumps of various shapes and sizes and typically lasts for only minutes to hours. While it can be very itchy, a person with hives will generally not scratch enough to break the skin and cause bleeding. Urticaria can be acute (lasting less than six weeks) or chronic (lasting more than six weeks). 

The swelling that sometimes goes along with urticaria is called angioedema. It often involves the lips, eyes, hands, and feet. In cases where angioedema presents at the same time as urticaria, the angioedema usually feels itchy. In cases where angioedema presents without urticaria, it can feel itchy or it may burn, sting, or cause a tingling sensation instead. In rare cases, severe swelling that blocks the ability to breathe can develop. This is a medical emergency known as anaphylaxis, which can be life-threatening.

When to See a Doctor

Contact your healthcare provider right away if you have a rash that appears suddenly, spreads quickly, or is accompanied by a fever. You should also seek care if you have a blistering rash near your genitals, on or near your eye area, or in your mouth, or if a rash shows signs of infection.

Allergy-Rash-Explainer-Hives-Chronic-Urticaria
DermNet NZ

Contact Dermatitis

Contact dermatitis happens when the skin comes into direct contact with a substance that causes a reaction. People react to a variety of chemicals, including cosmetics, hair dye, metals such as nickel, topical medications, and dental materials.

An example of contact dermatitis is a rash from poison ivy, which is extremely itchy and appears as blisters that ooze and crust after contact with plants of the Toxicodendron family.

A contact dermatitis rash may look like atopic dermatitis, but the rash is typically located only in the area of contact with the offending substance. Common locations include the face, especially the eyelids, neck, hands, and feet.

Contact dermatitis to metals, such as in jewelry or snaps/buttons/zippers on clothing, commonly occurs on the neck, wrists/hands, piercing holes, and at the waistline. Contact dermatitis can be diagnosed through a patch test, though it can be difficult to determine the point of contact with the allergen.

Allergy-Rash-Explainer-Contact-Dermatitis
DermNet NZ

Summary

Skin rashes can be alarming, particularly if you're having an allergic reaction to a substance you encounter in your daily life. Because there are different types of rashes, it's important to understand which type of rash you have and which treatment will work best.

If you do not have a history of skin allergies, it's important to work with a healthcare provider to learn what is causing your rash so you can avoid it and prevent future reactions.

Frequently Asked Questions

  • What is the main cause of a skin allergy?

    Skin allergies happen when we come into contact with certain substances and our body reacts to them. Nickel, a metal found in jewelry, clothing fasteners like zippers or snaps, and cell phones, is responsible for many skin allergies.

  • How do you treat a skin allergy?

    Treatment for skin allergies depends on the type of rash you have. Eczema, for instance, responds to topical ointments and moisturizers to reduce inflammation. Hives, on the other hand, can be treated with antihistamines such as Zyrtec or Allegra. Talk to your healthcare provider about your rash and which treatment would be best.

  • How can you prevent an allergic reaction of the skin?

    As with other allergies, the best way to prevent a reaction is to avoid contact with the substance you're allergic to. You can minimize your risk of having a skin reaction by taking steps that include choosing clothing or jewelry carefully, covering electronic devices, or wearing long pants and gloves while working outdoors.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Maliyar K, Sibbald C, Pope E, Sibbald G. Diagnosis and management of atopic dermatitis: A review. Adv Skin Wound Care. 2018;31(12):538-550. doi:10.1097/01.ASW.0000547414.38888.8d

  2. Kanani A, Betschel SD, Warrington R. Urticaria and angioedemaAllergy Asthma Clin Immunol. 2018;14(S2):59. doi:10.1186/s13223-018-0288-z

  3. American Academy of Dermatology Association. Rash 101 in adults: When to seek medical treatment.

  4. Martin SF, Rustemeyer T, Thyssen JP. Recent advances in understanding and managing contact dermatitisF1000Res. 2018;7:810. doi:10.12688/f1000research.13499.1

  5. American Academy of Dermatology Association. 10 Reasons your skin itches uncontrollably and how to get relief.

  6. American Academy of Allergy Asthma & Immunology. Skin allergy.

Additional Reading

By Daniel More, MD
Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and formerly practiced at Central Coast Allergy and Asthma in Salinas, California.