Overview of Sunscreen Allergy

Sunscreens, including those that are added to many cosmetics and lotions, may cause some people to have allergic reactions. Most of these allergic reactions represent contact dermatitis. If you have an allergic reaction to sunscreen, you can usually avoid the reaction by switching to another sunscreen that has different chemicals.

What Is Sunscreen Allergy?

Contact dermatitis is an itchy, flaking, red, and/or blistering skin rash, typically caused by the direct contact of a substance with the skin.

While contact dermatitis to sunscreens is not as common as cosmetic allergies, it is not a rare condition. The reaction to sunscreens can occur anywhere on the body where the substance is applied. It tends to be more common in the areas of the body with the most sun exposure. This is called photo-contact dermatitis.

Photo-contact dermatitis usually occurs on the bare, sun-exposed areas of the body. In some cases, however, clothed areas of the body can also be affected. The area of the neck under the chin is usually not affected.

Contact dermatitis to sunscreens can occur as a result of an allergy to the active ingredients or to the fragrances or preservatives in the product. 

There are two types of contact dermatitis, irritant and allergic. This difference is often difficult to tell apart, and the distinction can be made by allergy patch testing, which may be performed in cases when an allergy is being considered. Patch testing is an important part of the evaluation of contact dermatitis.

Who Is at Risk for Developing Sunscreen Allergy?

Those most at-risk for developing sunscreen allergy include the following groups:

• Females, possibly as a result of higher use of cosmetics containing sunscreens
• People with chronic sun-related skin conditions, such as sun-damaged skin
• People with atopic dermatitis
• People who have applied sunscreens to damaged skin
• People with outdoor occupations

How Do Sunscreens Work?

Sunscreens work in one of two ways:

• Chemical Absorbers: Most sunscreens absorb ultraviolet (UV) radiation (the energy from the rays of the sun) and turn this energy into a less dangerous form of radiation that causes less damage to the skin. There are sunscreens that absorb different types of UV radiation, such as UVA and UVB. Chemical absorbers include most of the available sunscreens that can be rubbed completely into the skin.
• Physical Blockers: These sunscreens reflect the sun’s radiation away from the skin so that it is not absorbed. Physical blockers include ingredients zinc oxide and titanium dioxide and are white or brightly-colored sunscreens frequently used on the nose and lips of beachgoers.

Which Chemicals in Sunscreens Cause Allergies?

Some of the active ingredients in sunscreens have the potential to cause contact dermatitis. Many sunscreens have multiple active ingredients, so it may be difficult to determine the exact cause without patch testing for individual chemicals. The following are the most common active ingredients in sunscreens that have been reported to cause contact dermatitis.

• Avobenzone. This rarely causes contact dermatitis.
• Benzophenones. Benzophenones have been used in sunscreens for decades, and are one of the most common causes of sunscreen-induced contact dermatitis in the United States. Other names for benzophenones include oxybenzone, Eusolex 4360, methanone, Uvinal M40, diphenyl ketone and any other chemical name ending with “-benzophenone”.
• Cinnamates. Cinnamates are less commonly found in sunscreens and are a common ingredient used as flavorings and fragrances in everything from toothpaste to perfumes. These chemicals are related to Balsam of Peru, cinnamon oils and cinnamic acid and aldehyde, so people allergic to cinnamates may also be allergic to these other chemicals. Other names of cinnamate-containing chemicals include Parsol MCX and any chemical ending with “–cinnamate.”
• Salicylates. Benzyl salicylate was the first sunscreen used in the United States. Common chemicals in this group used today include octyl salicylate, homosalate and any chemical ending with “-salicylate.” Salicylates can cause contact dermatitis.
• Dibenzoylmethanes. These sunscreens have been used in the United States and include the chemicals avobenzone and Eusolex 8020. They are frequently combined with other chemical absorbers in sunscreens.
• Octocrylene. Octocrylene is a relatively new chemical used in sunscreens. It has been reported to cause contact dermatitis. It is similar to cinnamates and may be used together with cinnamate chemicals in sunscreens.

Sunscreens for People With Sunscreen Allergy?

Physical blocking agents have only rarely been reported to cause contact dermatitis. These agents include zinc oxide and titanium dioxide and tend to come in heavier creams that do not absorb well into the skin. For this reason, some people do not like to use these agents, as they are less cosmetically pleasing. However, sunscreens containing these chemicals are a good choice for people with an allergy to sunscreens, or those with the concern of developing an allergy to sunscreens.