Careprost (Bimatoprost 0.03%) has a unique effect on the growth, the volume of your eyelashes and eyebrows, as a result of its use (eyelashes, eyebrows) become longer, thicker and darker. The active substance careprost is "bimatoprost" which affects the growth of hair. Careprost Eye Drops is a prostaglandin analog that is used for the treatment of increased fluid pressure inside the eye (intraocular hypertension) and open-angle glaucoma, a progressive condition that may eventually lead to vision loss.