A method for preventing hyperpigmented skin, undesired pigmentation disorder of skin, or undesired darkening of skin using coumarin compounds, the use of such compounds, and compositions and formulations thereof are disclosed. In a particular embodiment, the coumarin compounds are selected from robustic acid methyl ether, scandenin, and coumophos. The compounds may be prepared as additives to pharmaceutical and cosmetic compositions, and in personal care products such as antiperspirants. In a particular embodiment extends to an antiperspirant product containing a skin darkening inhibitory amount of a compound of the invention. Also, the present skin darkening compounds may be prepared in combination with each other. The compounds, compositions and formulations of the invention may be used for the prevention of the onset or progression of conditions characterized by unwanted skin darkening, including those that may be causally related to aberrant melanogenesis activity including, by way of non-limiting example, hyperpigmentation and others.
