My cfs doctor is starting me on lowdose naltrexone (ldn). She is having me start at .5 mg with the aim of getting me to 1.5 mg after a couple of weeks. I was just wondering what others have experienced with ldn, both positive and negative. My biggest problem has been exercise intolerance, and I am especially interested if any improvement has been seen in this regard. You can PM me if you don't feel comfortable posting in the forum.