Unoprostone is used to treat eye conditions, including glaucoma and ocular hypertension, in which increased pressure can lead to a gradual loss of vision. Unoprostone is used for patients who cannot use other eye medications for their condition or whose eye condition has not responded to another medication. Unoprostone is in a class of medications called docosanoids. It lowers pressure in the eye by increasing the flow of natural eye fluids out of the eye.