I've been using this serum on my sparse eyebrows twice a day for nearly a month now. I've tried other serums and didn't have high expectations but began to notice a difference after two weeks. This morning I went for a facial and the salon owner commented on my fuller brows. If there's a downside, it's the tiny brush. It didn't work for my eyelashes but is working brilliantly for my brows. Originally posted on www.theordinary.com