I have been experiencing severe weight loss (weight is 103, height 5'5") and weakness (on top of the regular CFS symptoms) for the last year and a half. I've had every test known to man and seen multiple doctors, but no one has been able to figure out why or be of help. I've been tested for parasites twice, but nothing showed up. I was tested for malapsorption, but the results were normal. I don't have anemia. My diet hasn't changed. When I went on antibiotics for a month earlier this year for an H. pylor infection, the weakness seemed to subside somewhat (although the weight loss was unchanged). About a week after stopping the antibiotics, the weakness came back. The antibiotics adversely affected my immune system, so I'm not anxious to try another type of antibiotic unless there's a clear reason for it. I also did some ozone therapy last year and that helped me feel stronger, but I had to stop it because it was damaging my lungs. So there does seem to be a pattern where some things that work on killing bugs seem to help. But I've tried lots of natural buy killers that haven't helped. So I'm at a loss as to what is going on. Does anyone know what kinds of things can cause weight loss and weakness in people with CFS?