I'm 43 and have been using Tretinoin cream for almost six months for acne. I have noticed over the past several months that light sunspots I had on my forehead have become much darker. Is that a result of using tretinoin? It's very frustrating that I've gone from one problem (acne) to another (sunspots). For the record, I have been using sunblock daily since I was in my 20s, I am definitely not a sunbather.