Notice a difference after about 3 weeks.
It seems to work.  I have been using this for about 3 weeks and notice longer lashes and thicker eyebrows.  I use it twice a day.  UPDATE:  I am on my second tube and I hope they do not stop making this stuff.  I have tried other serums but they burned my eyes.  This ones does not burn unless I actually drop it into my eye.  It has improved the length and health of my lashes and I seem to have more lashes when I curl them.  I am happy with this product and do not feel the need to purchase anything more expensive or that might work faster.
Rating: 5 stars