Why Using SPF With Tretinoin Is So Crucial by Musely Editors Why Using SPF With Tretinoin Is So CrucialSince tretinoin is working to undo damage caused by the sun, it makes sense that dermatologists recommend protecting skin treated with retinoids from the sun to help maintain results, as well as preventing undesirable effects. Here are three major reasons why you want to protect your skin from the sun when using tretinoin. 1. Your tretinoin won't be as effective Retinoids are photo-inactivated, meaning exposure to direct sunlight makes them less effective. For this reason, they are normally prescribed to be used at night, right before going to bed. The sun's UVA and UVB rays degrade tretinoin, so you won't get the full benefits of using this highly effective treatment. Since tretinoin work best over a long period of time, you should wear sunscreen and look forward to better skin. 2. It will make your skin more sensitive Because tretinoin helps replace older skin with fresh, new cells, skin treated with tretinoin is more prone to sunburn, especially in the first several weeks of use. Tretinoin should not be applied to skin that is sunburned or windburned, so you'll lose valuable treatment time, waiting until your skin is healthy enough to restart your skincare regimen if you experience a burn. 3. It increases the risk of skin cancer Exposing unprotected skin to too much UV radiation not only gives you a sunburn, it can cause changes in skin cells that lead to skin cancer. Sunburns may also increase your chances of developing melanoma, the most serious form of skin cancer, later in life. Because using tretinoin puts you at a higher risk for sunburn, you also run the risk of developing non-melanoma skin cancers, such as basal cell carcinoma and squamous cell carcinoma tumors, which develop most commonly in sun-exposed areas, such as the face and ears. Bottom line: Wear SPF when using tretinoin To keep your skin protected and get the best results from your tretinoin, wear sunscreen daily with an SPF of 15 or higher that protects you from both UVA and UVB rays.