One of my favorite products so far. It works best on open pimples, but I find that using it on any kind of pimple has some kind of positive effect; sometimes it flattens them or reduces inflammation, and other times it just keeps me from picking, which is even more important. I only bought one patch and now that I've run out I am feeling a bit panicked, but I guess that's how you know that a product is really good. Highly, highly recommend. I would suggest reading guides on how to use these patches (hydrocolloid bandages) if you're confused as to why they aren't working properly or are not absorbing the gunk the way you would expect them to.