Under the skin
The diagram below shows a cross-section of the skin in its normal, healthy state compared to skin with symptoms of eczema (also known as dermatitis). If skin loses moisture – including water, fats and oils – it becomes dry and irritants and bacteria pass through cracks to its deeper layers, causing irritation.
White blood cells and fluid rush to the area in response and an accumulation of white cells causes swelling and a rash, leading to further irritation and itchiness. The swelling can become chronic and the natural barrier of the skin compromised, which causes dryness and an uncomfortable and irritable long-term rash.