Within 6 weeks I had a noticeable improvement in my eyelashes. It does make my eyes a little itchy but no other significant side effects. My doctor provided a tiny brush which greatly helps control and stretch the product. I put a single drop in a metal spoon then use the brush to do both my lashes. I wash the brush and spoon in very hot water and let air dry. I'm going to experiment with an application every other day to maintain them.