HealthInfo West Coast-Te Tai Poutini

Overview of dermatitis (eczema)

Dermatitis is a very common skin condition which makes your skin dry, red and itchy.

Dermatitis, also known as eczema, is the name given to a group of conditions that cause inflammation of your skin.

Types of dermatitis

There are several types of dermatitis with the most common being:

• Atopic dermatitis (eczema)
• Allergic contact dermatitis
• Irritant contact dermatitis
• Seborrhoeic dermatitis and cradle cap. This mainly affects the scalp but can affect your face including eyebrows, ears and eyelids.

A red spotty rash called muzzle rash can occur around your mouth. This is also called periorificial dermatitis. But it is not dermatitis despite its name.

Causes of dermatitis

Causes of the most common types of dermatitis include:

• Atopic dermatitis (eczema). The exact cause is not known but it is believed to be caused by a combination of genes and triggers. People with atopic eczema have a lower amount of a protein called filaggrin that helps keep the skin barrier supple and healthy. People with atopic eczema also tend to have an overactive immune system. This can be triggered by a substance inside or outside the body, causing inflammation.
• Allergic contact dermatitis. This is due to an allergic reaction to a chemical or substance that you are allergic to (called an allergen).
• Irritant contact dermatitis. This occurs when your skin comes into contact with a substance that irritates it (called an irritant).
• Seborrhoeic dermatitis is caused by a yeast (fungus) that is in the oil secretion on the skin.

Dermatitis is not contagious. Food allergies do not cause dermatitis. But having an allergic reaction to food can cause it to worsen.

Diagnosing dermatitis

Your general practice team will usually diagnose dermatitis by seeing what your rash looks like. They will also ask you questions about it.

Treating dermatitis

The treatment depends on the type of dermatitis. It can include moisturisers, steroid creams, antifungal medicines and antibiotics.

  HealthInfo recommends the following pages

• DermNet NZ – Dermatitis

  This page explains what dermatitis is, types of dermatitis and how it is treated.

Written by HealthInfo clinical advisers. Last reviewed February 2025.

Sources

Page reference: 885841

Review key: HICOD-326084