Jaquta is right..there is no long term pharmacological answer that is safe. The obsession and compulsion is part of your mind function, and there are very good ways to deal with that...the shrinkyourself program Jaquta mentioned is based on my book, it is online self help therapy, that is designed to get to the source of the overeating compulsion...check it out.
A similar question was asked on the Weight Loss and Healthy Lifestyle expert forum. The doctor was unaware of any medication to suppress appetite.
I have heard that protein can help to suppress appetite. Have you tried filling foods such as fruits and vegetables, lean meats, poultry, fish, eggs, low-fat milk and dairy products, etc?
Usually behind compulsive eating are emotional issues. You might like to check out the doctor's website: shrinkyourself.com.