Careprost eye drops 0.03% (applied with a brush) 3ml eye drop is used to treat eyelash hypotrichosis, which is a condition in which there are not enough eyelashes. It contains Bimatoprost, a prostaglandin analog that successfully promotes lash development, making lashes thicker and longer. The pharmaceutical substance is quite similar to prostaglandins, a natural chemical in the body that is used to increase the density, thickness, and color of the eyelashes. It is frequently used since it has few negative effects and is quite effective.