I would be interested in hearing from those who have had documented moderate to severely low DHEA levels and subsequent response to supplementation. If it was helpful, specifically in what way did it help, e.g. improved fatigue, memory, etc.? I am currently reading an interesting book, "On Hope and Healing" by Neil Nathan, MD. It deals with chronic illness in general. It certainly addresses CFS but is not specifically about CFS. He discusses various things to look at such as magnesium deficiency, thyroid, methylation cycle, etc., but the first thing he discusses is DHEA. He goes so far to say that if he could only utilize one lab test and treatment for patients with chronic illness, his choice would be DHEA. He explains normal levels, how they correspond to age, etc. My son has CFS with POTS/NMH to a disabling degree. As I was reading this chapter, I remembered that at one point someone had ordered an adrenal steroid profile. When I pulled it out I was astounded by the DHEA level as in light of the information provided in this chapter his DHEA was astonishingly low at that point, not even 10% of where it should be. I am definitely going to see if we can have this checked again and see what it is currently. If it is anywhere close to that, I would think that supplementation would almost certainly have to be of at least some benefit. I have been searching on the Net meanwhile and have also learned of some adverse reactions in some patients. It seems that these sometimes occur after an initial positive reaction. I am very curious to hear of personal experiences here. It would also be helpful to know the degree of deficiency before starting supplementation as I suspect that perhaps the reaction, positive or negative, possibly partially depends on the degree of deficiency to begin with and perhaps getting the level too high during supplementation if it is not monitored. Thanks so much for sharing.