I used these on a dark patch of postinflammatory hyperpigmentation that I developed after a laser treatment for a sunspot. Spoiler, the laser treatment only made it worse, so I'm trying to get rid of the now darker and larger spot by other means. I started with minimal expectations since this product is not necessarily made for this purpose. Using these patches I noticed the spot fading after one box. I will likely purchase again because it seems to speed the process🎉🎊