Stand up to that bully mascara! If you're a regular mascara wearer, you know the effect mascara can have on your natural lashes. Some formulas dry them out and make them look shorter and brittle once the mascara comes off. Don't worry. Mascara primers to the rescue! These specially formulated conditioners prep the lashes with conditioning ingredients. For example, Smashbox's Layer lash primer uses panthenol to strengthen and make lashes more durable.