Sunscreen for lips, inner canthus key to preventing photodamage

August 1, 2011

Sun protection for the lips can prevent skin cancer and aesthetic loss of the defined vermilion border. Leukoplakia can also be prevented through sunscreen use, and some precancerous lip changes can even regress with photoprotection.

Key Points

Q. What is the best sunscreen for the lips?

A. Sun protection for the lips can prevent skin cancer and aesthetic loss of the defined vermilion border. Leukoplakia, sometimes the analog of an oral actinic keratosis, can also be prevented through sunscreen use, and some precancerous lip changes can even regress with photoprotection. Sun protection for the lips, without a reflective stratum corneum, is vitally important.

These products are opaque and totally block UV access to the lip. For women with extensive lip photodamage, they are an excellent sunscreen. They do not contain any sunscreen ingredients and do not have an SPF rating, but anything that blocks UV and visible radiation from reaching the lip tissue functions as a sunscreen.

The only problem with the new long-wearing lipsticks is that they can create cheilitis, as they are just a polymer film with no moisturizing ingredients. Many of these lip products come with a lip gloss that is applied after the polymer has dried. These lip glosses do not add to lip photoprotection.

A better solution is to purchase a complimentary color lipstick, which is also opaque, and apply this over the long-wearing lipstick. This provides moisturization and another layer of photoprotection. Lip cosmetics should be considered as an option for women with lip photodamage.

Q. How can cosmetics decrease the formation of basal cell carcinoma at the inner canthus?

A. The inner canthus of the eye and the medial nasal bridge are common locations for basal cell carcinomas. This seems rather surprising, since this is a facial concavity with little direct sun exposure.

In actuality, light bouncing in and around the orbit is focused on this area, explaining the propensity for cancer formation. It is actually light that bounces off this tissue that accounts for the medial location of pterygium, the ophthalmologic equivalent of an actinic keratosis.

Many patients forget to put sunscreen around the medial canthus and surrounding tissue, and others find that sunscreen in this location burns when it enters the eye. Sunglasses are an excellent way to protect this tissue in both sexes, but only the large-lens varieties are effective.

Another alternative is to put cosmetics in this location to shield the skin. For women, the use of high-coverage facial foundations, facial concealer creams, translucent powders or eye shadows may be helpful. For men, the use of a stick sunscreen or a sunscreen containing lip balm could be considered. The stick products have a higher wax content, which is less likely to move into the eye during activity and sweating.

These are suggestions that can be offered to the patient experiencing recurrent basal cell carcinomas in this area. There is little that can be done to change the architecture of the face and the light reflection around the eye. Wearing a wide-brim hat is also a solution, but patients seem hesitant to adopt this solution.

Zoe Diana Draelos, M.D., is a Dermatology Times editorial adviser and consulting professor of dermatology, Duke University School of Medicine, Durham, N.C. Questions may be submitted via e-mail to zdraelos@northstate.net
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