"i have lost 88 pounds in 10 months. i had some drowsiness and increased sweating at first but improved within a few weeks.. a small price to pay for the overall improvement in my quality of life. i believe the effectiveness depends upon the underlying reason for obesity. naltrexone lowers cravings and improves addictive behavior. my problem was the compulsion to binge eat high calorie foods. i don&#039;t know how effective it would be on obesity for other underlying reasons, which may explain why it works for some and not for others. my life has improved and i can do things i have been unable to do in years. very pleased!"