What causes sunscreen reactions?
Reactions to sunscreen are rare. They occur in a very low proportion of the population, fewer than 1% of all users. While uncommon, reactions can be upsetting for those affected.
They can be a result of a sensitivity or allergy to any of the ingredients used in these products. Some people may have a reaction to a fragrance, preservative, UV absorber or another component of the sunscreen.
Sensitivities to sunscreen are complex and can range from mild to severe. Reactions can be linked to other co-factors as well, like sunlight or other allergens. Using sunscreen with some medications or other tropical creams and lotions can also cause reactions.
Some reactions occur soon after applying the sunscreen, while others (e.g. allergic reactions) can develop after a couple of days or even years of using the same product.
As with all products, use of sunscreen should cease if an unusual reaction occurs. Individuals or families experiencing reactions should seek a referral to a dermatologist to understand what may have caused the reaction and gain advice on ingredients that should be avoided in the future.
What are the different types of reactions?
Contact dermatitis
The most common sunscreen reaction is called “contact dermatitis” and occurs in people who have a sensitivity to an ingredient found in sunscreen or cosmetics with a sunscreen component. There are two types of contact dermatitis – irritant and allergic.
Irritant contact dermatitis
Irritant contact dermatitis is a reaction that can occur after applying sunscreen and is more common in people who have a history of eczema or sensitive skin. It causes an irritation in the skin where the sunscreen was applied, and can appear as mild redness or as a stinging sensation (without any redness).
Allergic contact dermatitis
Allergic contact dermatitis is the less common type of contact dermatitis and occurs in people who have developed a sensitivity to an ingredient found in the sunscreen or cosmetics with SPF protection. This reaction is the result of an allergy to an ingredient, such as fragrances or preservatives, and can occur even if you haven’t had a reaction to these ingredients or sunscreens in the past, as allergies can develop over time. An itchy, blistering rash occurs on skin where the product has been applied, and can sometimes also spread to other areas.
Photocontact dermatitis
A rarer type of sunscreen reaction is called ‘photocontact dermatitis”. This type of reaction usually occurs where the product has been applied to the body and exposed to sunlight. In some people, there is an interaction between a sunscreen ingredient and ultraviolet light which leads to a skin reaction. This is usually a result of an allergy to the active ingredients, but it can also be due to a reaction to the fragrances or preservatives in the product. The reaction may look like severe sunburn or eczema, and most commonly occurs on the face, arms, back of hands, chest and lower neck.