Apply Careprost eye drops for lashes on your lower eyelid using a brush. When applying it, take care not to get the solution on other areas of your skin. Use the solution as directed for the duration of your prescription. If you want a full effect, do not miss any doses; it will take four weeks to show results. Careprost eye drops growth solution can be combined with other eye products, however they should be given at least 5-10 minutes apart.