woman with eczema on her back

Irritant vs. Allergic Contact Dermatitis: Understanding Differences


A woman scratching her back


Contact dermatitis results in an itchy rash caused by either direct contact with something (irritant contact dermatitis) or an allergic reaction to it (allergic contact dermatitis).


While the symptoms and treatments for the two conditions are similar, there are some distinctive differences. We’ll explore these differences and discuss how the two types of contact dermatitis are caused, their symptoms, treatments, and more.


Related: Psoriasis vs. Seborrheic Dermatitis


What Is Irritant Contact Dermatitis?


Contact dermatitis happens when your body reacts to exposure to certain substances, triggering skin irritation or an allergic reaction.


The most common type is irritant contact dermatitis — a nonallergic reaction that occurs when something irritates and damages your skin’s outer layer.


Some people react to irritants after a single exposure, and others can develop rashes after being repeatedly exposed to more mild irritants. Some people may develop a tolerance to the substance that irritates them over time.


Irritant Contact Dermatitis Symptoms


Irritant contact dermatitis causes slightly different symptoms than allergic contact dermatitis, including:

  • Blistering and cracking skin
  • Extreme dryness
  • Skin that feels tight or stiff
  • Swelling
  • Open sores that form crusts
  • Ulcerations 

Irritant Contact Dermatitis Causes


As we mentioned above, irritant contact dermatitis is more common than allergic contact dermatitis — it happens when your skin comes into contact with a toxic or irritating material.


Many different substances can cause a reaction, including:

  • Bleach
  • Kerosene
  • Pepper spray
  • Battery acid
  • Drain cleaners
  • Detergents


Less harsh materials can also cause irritant contact dermatitis when you come in contact with them too often; soap and water can even cause a reaction if you scrub your hands too often, for example.


In addition, people who frequently have their hands in water — like hairdressers and healthcare workers — often experience this type of contact dermatitis in their hands.


What Is Allergic Contact Dermatitis?


Allergic contact dermatitis is a little different — it occurs when you come into contact with something you’re sensitive to, causing an immune reaction in your skin. This reaction only affects your skin that came into contact with the substance.


However, various other things — like foods and medicines — can also trigger allergic contact dermatitis as they enter your body.


People often get sensitized to these allergens after coming into contact with it many times over the years. Then, once you develop an allergy to any substance, even small amounts of contact can cause you to have a reaction.


Allergic Contact Dermatitis Symptoms


The symptoms of allergic contact dermatitis vary, but common indications include:

  • Dry, scaly, and flaky skin
  • Oozing blisters
  • Dark or leathery skin
  • Extreme itching
  • Swelling (particularly in the face or eyes)
  • Hives
  • Red skin
  • Burning skin
  • Sun sensitivity 



A poison oak plant

Allergic Contact Dermatitis Causes


Allergic contact dermatitis happens when your skin develops an allergic reaction from getting exposed to a foreign substance. That exposure causes your body to release different inflammatory chemicals, making your skin feel irritated and itchy.


Related: Eczema Causes and Treatments


Almost anything can cause an allergic contact dermatitis reaction — some common causes include:

  • Nickel and gold jewelry
  • Chemicals and perfumes found in skin care products and cosmetics
  • Latex gloves
  • Poison ivy and poison oak


Diagnosing Irritant & Allergic Contact Dermatitis


If your contact dermatitis symptoms don’t improve over time or are severe, you should contact your doctor. They will examine your skin and go through your medical history, asking questions like:

  • What makes your symptoms go away or worsen?
  • What products do you regularly use on your skin?
  • What do you do for a living?
  • When did your symptoms first appear?
  • Were you in a new environment when the symptoms started?
  • Are there any chemicals you come into contact with every day?


If your contact dermatitis is related to allergies, your doctor might refer you to an allergist. On the other hand, if it’s related to irritants, they might refer you to a dermatologist. Either way, these specialists can help pinpoint what’s causing your contact dermatitis. 


Treating Irritant & Allergic Contact Dermatitis


In most cases, irritant and allergic contact dermatitis symptoms will go away once your skin is no longer in contact with the substance that bothers it.


You can also try these self-care strategies at home:

  • Clean your skin using lukewarm water and a mild soap to remove any irritants
  • Apply petroleum jelly — like Vaseline — to the affected area.
  • Take an antihistamine — like Benadryl — to help relieve itching and reduce your allergic response
  • Avoid scratching the irritated area — this can make it worse and possibly cause an infection
  • Quit using any products that you think might be causing the issue
  • Use an anti-itch cream like hydrocortisone or calamine lotion


Most people can find relief from their contact dermatitis with these tips and items from their local drugstore. 


Contact dermatitis, whether it’s from an irritant or allergy, isn’t usually cause for concern. 


However, if your rash doesn’t improve, covers a large part of your body, or is close to your mouth or eyes, you should contact your doctor. They can prescribe a potent steroid cream if home treatments aren’t enough to soothe your skin.


Preventing Irritant & Allergic Contact Dermatitis


The best way to prevent contact dermatitis is to avoid exposure to irritants and allergens. You can try these tips to prevent contact dermatitis:

  • Identify the causes of your rash and avoid them. For example, if body jewelry bothers you, wear jewelry made of hypoallergenic materials, such as gold and surgical steel.
  • Wash your skin after contact. Use mild, fragrance-free soap and lukewarm water, rinsing completely. You should also wash any items or clothing that also came into contact with the irritant. This tip is particularly helpful if you come into contact with poison oak or ivy.


Related: What to Avoid With Sensitive Skin


  • Wear protective clothing. You can use masks, gloves, and goggles to protect you from irritating substances like household cleaners.
  • Use iron-on patches to cover metal on your clothing. Some people have a contact dermatitis reaction from the small pieces of metal commonly found on clothing, especially jeans.
  • Apply barrier gels or creams. Using these products can give you a protective layer to protect from allergens and irritants. Creams containing bentoquatam are especially helpful for protecting against poison ivy.
  • Use moisturizer regularly. Applying a moisturizing lotion can help keep your skin supple, protecting and restoring your skin’s outer layer.


Are you using the right moisturizer for your skin? Learn why your skin’s pH matters and find the right fit for your skin here.