Careprost eye drops should be used to the affected eye as directed by a doctor, usually once a day in the evening. A doctor should decide on the right treatment plan and dose because these things depend on the patient's health and medication response. Pull down on the lower eyelid and lean the head back slightly to create a tiny pocket for the eye drops. Holding the dropper above the afflicted eye, squeeze a drop of medication into it and close Careprost eye drops. Press a finger gently on the inner corner of the eye for about a minute to stop the liquid from running out of the tear duct.