How long does Latisse last?, asks a RealSelf user. “Are results permanent?”.When used daily along the upper lash line, studies show at sixteen weeks there is an average of 50% improvement in the lenght and thickness of lashes, Aristocrat’s certified surgeon Dr. Kevin Tehrani, M.D., F.A.C.S. “First you will note increase in length followed by fullness. After the sixteen weeks …