I have awfully red/dark knees and I've been wanting to whiten them forever. This cream was relatively cheap so I bought it. When applied, there is a slight tingly sensation and feels kind of cool. The effect isn't immediate, I have been using this cream for around 2 weeks and my knees only lightened a little. The good thing is, it's easy to spread and you only need a little bit each time, so it will definitely last