Careprost eye drop is used to prevent pressure build-up throughout. Careprost bimatoprost ophthalmic solution is not recommended for breastfeeding women. Consult your doctor before using this medicine. The effect of this drug on the eye form lasts for an average of 12 to 6 hours. The effect is seen within 4 hours after taking this medicine and can be seen within 2 months of starting the first dose.