Phos.Serine did a number on me. It changes the sensitivity of the HPAA, and people I know say my personality even changed as a result of taking it. I think it contributed to my development of CFS through alteration of the hypothalamic/cortisol feedback mechanisms. There is no way I would take a supplement with PS now, and I think it's all but crazy for anyone with hypoadrenal issues to take it. There are other nutrients that can repair mitochondrial membranes without having to resort to seriphos. jmho.