Which ingredients are commonly associated with photosensitivity and what protective measures should be advised post-treatment?

• A. Vitamin C, niacinamide; wear sunglasses and stay indoors.
• B. AHAs (glycolic), retinoids, some essential oils; sunscreen with broad-spectrum protection, limit sun exposure, wear protective clothing, and avoid tanning beds.
• C. Selenium sulfide; avoid washing face for 24 hours.
• D. Salicylic acid only; no sun precautions needed.

Answer: (B)

Photosensitivity occurs when certain skincare ingredients or treatments temporarily make the skin more vulnerable to UV light. AHAs like glycolic acid and retinoids increase cell turnover and can thin or disrupt the skin’s protective barrier, raising the risk of sunburn and pigment changes. Some essential oils, especially citrus-derived ones, can be phototoxic in sun exposure. Because of this, post-treatment guidance emphasizes strong sun protection: use a broad-spectrum sunscreen to shield against both UVA and UVB rays, apply it generously and reapply regularly, limit sun exposure, wear protective clothing such as long sleeves, a wide-brimmed hat, and sunglasses, and avoid tanning beds. These measures help prevent irritation, burns, and pigment issues while the skin recovers.