Currently, there is a wide range of sunscreen brands available in the market. These sunscreens typically contain various active chemicals that either absorb or block harmful UV rays, as well as fragrances, preservatives, and a base like lanolin. With the increasing popularity of sunscreen use in recent decades, it is not surprising to observe cases of allergic contact dermatitis caused by these products.

Allergic contact dermatitis can occur in individuals who are allergic to any of the ingredients present in sunscreen products or cosmetics that include sunscreen. The resulting rash can appear anywhere on the body where the substance has been applied and sometimes may even spread to unexpected areas. Moreover, individuals may have a sensitivity to the fragrances and preservatives found in sunscreens. 

In certain cases, sunscreen allergy can lead to a condition called photocontact dermatitis, where the affected areas typically follow a pattern of sun exposure and coincide with the application of sunscreen. These areas often include the face, arms, backs of the hands, a “V” shaped area on the upper chest, and the lower neck. Usually, the upper eyelids, area under the chin, and behind the ears remain unaffected. 

Due to the presence of multiple active ingredients in sunscreen products, it can be challenging to identify the specific cause of dermatitis. Patch testing for individual components is the only reliable method to determine the allergenic chemical.

Allergies to sunscreen products often stem from the inactive components like fragrances or preservatives used in them. Patch testing using fragrance mix and Balsam of Peru can detect approximately 75% of fragrance allergy cases. A positive patch test to fragrance mix indicates an allergy to one or more fragrance chemicals. It’s estimated that 1-2% of the general population is allergic to fragrance.

Self-testing a sunscreen product for allergies is possible but should be done under the guidance of a doctor. Apply a small amount (about the size of a 50-cent coin) of the product to a small, sensitive area of skin like the bend of your arm or neck for several consecutive days. Monitor the area daily, and if no reaction occurs, it is unlikely that you are allergic to it. However, it may still cause irritant contact dermatitis, so caution is advised.

Once dermatitis appears on the skin, treatment is similar to that for any acute dermatitis or eczema. This includes using topical corticosteroids, emollients, and treating any secondary bacterial infections, such as Staphylococcus aureus.

To prevent sunscreen allergies, it is best to avoid all products that contain substances to which you are sensitive tp. If you have a sunscreen allergy, metal oxide sunscreens like titanium dioxide and zinc oxide may be suitable options. These have not been reported to cause allergic contact dermatitis and are considered safe and effective sunscreen agents, despite being less cosmetically appealing. Your dermatologist can provide specific advice, especially if you are highly sensitive to sunscreen products.