Mate harehare pānga pāwera Allergic contact dermatitis

Allergic contact dermatitis is due to an allergic reaction to a chemical or substance. Many things can cause this. The most common are:

• nickel (found in many everyday item such as jewellery, coins, keys and zips)
• rubber (latex)
• hair dyes
• some plants (such as ivy).

Chemicals in make-up, soap, skincare products and plasters can also cause it.

Often people do not know or cannot work out what it is they are allergic to and what is causing their dermatitis. 

It is different to irritant contact dermatitis. Irritant contact dermatitis can affect anyone. But you will only get allergic contact dermatitis if you are allergic to certain things that touch your skin.

Irritant contact dermatitis

If you have allergic contact dermatitis, you will develop an itchy rash after coming into contact with the allergen. For example, you might get a rash: 

• on your eyelids if you are allergic to a chemical in your make-up
• under your watch strap if you are allergic to nickel.

The rash usually happens a few hours after the contact. IT might be very itchy.

Itching (pruritis) (internal link)

Your skin can become red, sore and swollen. This will settle down after a few days as long as your skin is no longer in contact with the allergen.

Contact your healthcare provider if your skin:

• blisters
• itches constantly 
• does not stop being red, sore or swollen.

Any type of dermatitis can get infected, especially if you scratch it. If your dermatitis has become more red and painful, see your healthcare provider. They may prescribe an antibiotic.  

Your healthcare provider can usually diagnose allergic contact dermatitis by the appearance of your skin. They will ask you questions about your symptoms, including:

• when your symptoms first appeared
• what you were in contact with
• what made the symptoms worse.

They will try to identify the allergen with your help.

Laboratory tests are not usually required. But if it is not obvious what the allergen is, you might be referred to see a dermatologist (skin doctor) for patch testing. 

Patch tests — DermNet (external link)

Testing at home

If you think your make-up or skincare products are causing allergic contact dermatitis, you can test them at home with a simple test.

Put the product on a small area of sensitive skin (such as the inside of your upper arm) twice a day for 5 to 10 days in a row. If you get a rash there, it is likely you have allergic contact dermatitis.

This is called the open user test. It is a useful way to check your products so you can stop using anything that causes problems.

• Avoid contact with whatever you are allergic to. This is the main treatment for allergic contact dermatitis.
• Use topical moisturisers (emollients) on any affected area. These moisturise your skin to help rehydrate it and provide a barrier that helps your skin heal.
• Apply an anti-inflammatory steroid cream with 1% hydrocortisone. This may help to settle your skin down more quickly.

Ask your pharmacist for advice on what cream is best for you. You may need to see your healthcare provider to get stronger steroid creams. In severe cases you may need steroid tablets.

The best way to prevent allergic contact dermatitis is to avoid known allergens. 

If you cannot avoid known allergens:

• wear protective clothing, especially gloves, when handling 
• use barrier creams or gels to protect your skin
• choose fragrance-free moisturisers
• use fragrance-free or dye-free soaps, body washes, shampoo and conditioner
• wash your hands as soon as possible.