Allergic contact dermatitis

Allergic contact dermatitis refers to an allergic response that is caused by contact with certain substances. This type of hypersensitive reaction requires the skin to become sensitized to the substance first, which is why there is no allergic reaction when the allergen is first touched. Dermatitis is a general term used to describe various types of skin inflammation that are not harmful or dangerous. Allergic contact dermatitis is not contagious or hereditary, but people prone to allergies may be more at risk of developing this condition.

Allergic contact dermatitis: two phases

Allergic reactions typically manifest in two phases.

  1. The first phase is the acute phase, characterized by redness, swelling, and blisters. Once the blisters have healed, the skin becomes dry and scaly.
  2. This scaliness increases during the chronic phase although redness is reduced. The skin also becomes thicker and drier during the chronic phase and may crack along the Langer’s lines.

Several factors affect your chances of developing an allergic reaction. A substance’s structure plays a critical role in allergies as does your skin’s overall health as this will influence how quickly and when you develop an allergic reaction. Skin damage or eczema increase your chances of developing an allergy.

A person who develops an allergic reaction to a substance will most likely retain this hypersensitivity for the rest of their life. This means even small amounts of the substance will trigger an allergic reaction.

How do you identify allergy triggers?

The only way to identify allergy triggers is by having your hospital or GP administer a patch test. The test results will reveal which allergens need to be avoided to prevent an allergic reaction from occurring. We also recommend carefully reading ingredient labels to check for allergens before purchasing a product.

Key allergens

There are countless allergens that could trigger allergic contact dermatitis. Some of the most common culprits include:

  • aromatics and synthetic aromatics such as those found in home fragrances, perfumes, and cosmetics
  • preservatives such as those used in cosmetics and hand creams
  • base metals such as nickel
  • rubber and adhesives
  • medicines
  • plants

Allergy Certified products


Statistical data reveal an increasing incidence of allergic contact dermatitis compared with the past. Allergic contact dermatitis used to be a condition primarily affecting older women who had used the same perfume all their lives. It was therefore sometimes referred to as an ‘old woman’s disease’. Nowadays, this allergy is showing up on men and women of all ages and, unfortunately, it appears to be on the rise among children as well. Once a person has developed an allergy to a particular substance, they will retain this hypersensitivity for the rest of their life. This is why high-risk substances and allergens should be avoided at all costs. It can be tricky trying to understand the labels on cosmetic products and cleaning products as they often contain complicated-sounding ingredients. Fortunately, the Danish company Allergy Certified has made things easier in this regard, as they only certify products that do not contain any high-risk substances or allergens. This is very reassuring as it means any product bearing the Allergy Certified label is safe to use.

Can allergic contact dermatitis be prevented?

Allergic contact dermatitis cannot be completely prevented, just as it cannot be completely cured. Eczema is a case in point as flare-ups are not solely restricted to contact with allergens, but can be brought on by water and sweat as well.

This is what makes prevention so challenging. Nevertheless, avoiding allergens as much as possible from a very young age has a positive effect. Allergic contact dermatitis is on the rise among babies and young children and the most common allergens are fragrances and parabens. This is why we recommend using hypoallergenic products for both children and adults as these products do not contain any allergens.