Contact dermatitis: causes and symptoms

By Cristiano Antonino On Dec 1, 2022

Contact dermatitis is triggered when a substance recognised as ‘adverse’ comes into contact with the skin, triggering a defence reaction that stimulates an inflammatory and itchy immunological response from the body

Contact dermatitis: the causes

Contact dermatitis – also called contact eczema – is generally caused by the interaction of the skin and mucous membranes with an irritant substance or allergen.

The former is called irritant contact dermatitis and is the most common type of dermatitis, where the outer skin cells are damaged by direct exposure to substances with an irritant action, such as solvents, detergents, soaps, bleach, hair dyes, wool, etc.

Allergic contact dermatitis, on the other hand, is an inflammatory process of the skin triggered by an immune reaction in hypersensitive individuals exposed to an allergen they have previously come into contact with.

The most common allergens are contained in cosmetics, personal care products, perfumes, detergents, drugs, pollen, chemicals such as nickel, etc.

How does contact dermatitis manifest itself?

Irritant contact dermatitis usually occurs on areas of the body that have been directly exposed to the substance, with the appearance of

rough and tight skin
swelling, pain and burning
erythema, blisters and vesicles.

Symptoms associated instead with allergic contact dermatitis include sudden skin manifestations characterised by:

redness, burning and abrasions
hives and extreme itching
swelling, especially of the eyes and face.

Unlike the irritative forms, the manifestations of allergic dermatitis are not localised only in the area of contact but may later extend to other regions of the skin apparently not exposed to the allergen.

When to contact a doctor?

Most cases of contact dermatitis regress spontaneously within about three weeks, provided the substance that caused the rash is avoided.

If, on the other hand, symptoms develop worsening over time, become more widespread, show signs of infection or create severe discomfort in performing normal daily activities, it is essential to consult a doctor.