Oxybenzone reaction in sunscreen could be cause of allergy complaints

Key Points

Q. Why am I seeing an increase in patients who claim they are allergic to sunscreen?

For female patients with severe sunscreen allergy, pigmented sunscreen powders may be a possibility. These powders do not stay on well under high-humidity conditions or with water contact, but they may provide day-to-day sun protection. The combination of the talc, iron oxide and zinc oxide provides an SPF of 15. They brush on the skin easily, but they also brush off. It is best to apply them over a moisturizer for longer wear, but frequent application is required. Even a standard face powder can be used for sun protection, but the SPF will only be around 8.

A. Body washes are basically a liquid beauty detergent bar, but they can both cleanse and moisturize simultaneously. While it may seem impossible that a cleanser could accomplish both activities, think about the 2-in-1 shampoos that both cleanse and condition. Body washes are very similar in composition to these conditioning shampoos.

Cleansing occurs when the concentration of detergent is high and the concentration of water is low, while moisturizing occurs when the concentration of detergent is low and the concentration of water is high. During application of the body wash on a puff, to break the emulsion and incorporate large amounts of water and air, the body wash foams abundantly and is rubbed on the body. This is the cleansing step. The bather then steps into the shower spray to wash away the detergent, thus decreasing its concentration and increasing the concentration of the water. This is the moisturizing step. During the rinse phase, vegetable oils and dimethicone are left behind on the body to moisturize the skin while the detergent attached to sebum and environmental dirt wash away.

Body washes are two-phase liquids containing water-soluble and oil-soluble phases that are held together in a stable emulsion. When the puff breaks the emulsion, the water-soluble phase containing the detergent removes the dirt from the body and the oil-soluble phase remains behind to moisturize the skin.

Q. What's new in topical wound and scar management?

A. New wound-healing and scar-management products have entered the consumer market. One formulation combines a sulfur-containing onion extract designed to deliver antibacterial and anti-inflammatory benefits, with a sunscreen. Another new device approach employs a reusable occlusive bio-enriched polymer silicone-free gel patch. The round patch is self-adhesive and can be reused for several weeks.

The bio-enriched ingredients include linoleic acid, retinyl palmitate, phytosterols, ceramides and bisabolol. It is thought that the patch acts by modulating collagen synthesis and restoring epidermal function through addition of barrier lipids. The occlusive patch enhances delivery of the ingredients by hydrating the stratum corneum and delivering the barrier-repairing linoleic acid, phytosterols and ceramides. The bisabolol is a chamomile extract with botanical anti-inflammatory properties combined with retinyl palmitate as an antioxidant.

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