Abstract: The present invention provides for the use of an NMDA receptor antagonist, preferably memantine or neramexane or a pharmaceutical acceptable salt or a prodrug of said antagonists, in the preparation of a pharmaceutical composition for the prevention, amelioration and/or treatment of disorders of metabolism influencing body weight, in particular obesity, an eating disorder and/or in the regulation of appetite. Furthermore, the present invention provides for a method for the prevention, amelioration and/or treatment of disorders of metabolism influencing body weight, in particular obesity, an eating disorder and/or in the regulation of appetite comprising the step of administering to a subject in need thereof a therapeutically effective amount of an NMDA receptor antagonist, preferably memantine or neramexane or a pharmaceutically acceptable salt or prodrug of said antagonists.