I had moderate to severe acne to begin with and after 3 weeks of use my forehead is almost clear, and there is a lot less acne on my cheeks (mild to moderate now and fluctuates a bit). The blue light didn't clear my face up completely but it isn't meant to do that, and I'm really happy with the improvement. The instructions booklet says you can't use it on severe acne but what it really means is that you shouldn't replace treatment with the blue light. If you have severe acne then try it, but use other medications along with it (don't use it if you're using accutane though).
we are seeing improvement, no more ointments or pills! most acne gone... but still has scarring from past acne, so we are starting retin a today. cost... but worth it. slow, but is working! on 7th week. we finally found something that is killing the bacteria without taking oral antibiotics or using ointments that were drying and burning to him.