I saw my doctor on Monday and she said I probably have a seratonin imbalance. (Seratonin is a brain hormone that mostly regulates mood, but also other stuff.) I asked if that was still possible even though I don't feel depressed, and she said yes. So I've been taking Lexapro and I feel SO much better. I'm back maybe 90% and it's only been a few days. (She told me I might have to wait 10 days to see results so your mileage may vary.) I don't know if this means I never had CFS or if seratonin imbalance might be one cause of CFS. I remember many of you complaining that your doctor tried to give you antidepressants when you weren't depressed, but hey if it works and has no side effects why care that it's an antidepressant! Unless you've already tried it, it's worth a shot. She said in 6 months I can go off it. Some people have a more chronic problem and have to be on it the rest of their lives, but that's more rare.