We understand that using Tretinoin can sometimes be confusing, especially when it comes to sun sensitivity. Let us clarify a few things for you. Firstly, Tretinoin is a powerful medication used to treat various skin conditions, including acne, fine lines, and wrinkles. It works by increasing skin cell turnover, which can make your skin more sensitive to the sun's harmful rays. If you are experiencing sunburn after being outside for only 20 minutes in winter, it's possible that Tretinoin is making you more photosensitive. However, it's important to note that sunburn can occur even in low UV index conditions, particularly if you have fair skin or are particularly sensitive to the sun. In terms of the actual photosensitive damage caused by this exposure, it's difficult to say without examining your skin. However, any amount of sun exposure can potentially cause damage, so it's always important to protect your skin with a broad-spectrum sunscreen and avoid direct sunlight whenever possible. As for whether Tretinoin is causing more harm than good, we believe that when used correctly and in conjunction with proper sun protection, the benefits of Tretinoin far outweigh the risks. However, if you are concerned about sun sensitivity, we recommend speaking to your dermatologist, who can advise you on the best course of action for your particular skin type and condition. In conclusion, Tretinoin can make your skin more sensitive to the sun's harmful rays, but this doesn't necessarily mean that it's causing more harm than good. By taking proper sun protection measures and consulting with your dermatologist, you can safely continue to use Tretinoin and enjoy its many benefits.