There have been assorted threads on histamine that has renewed my interest in the possible contribution of histamine to my symptoms. I have tried H1 and H2 blockers with no obvious effects other than a mild reduction in my GERD. I looked up H3 antagonists and the wikipedia entry on it was fascinating to me. H3 antagonists appear to help sleep disorders, ADHD, overeating, and neuropathic pain. There is research underway to see if it can help modulate wakefullness. Has anyone tried an H3 antagonist? What I can't tell is whether the existing H3 antagonists are all for research, or whether some are available OTC, or at least via prescription. I realize that the methylation protocol should help with breakdown of histamine, but I've taken metafolin, methyl b-12, and other co-factors for 9 months with no significant effect. Until I can determine what is blocking my recovery, it would be great to have something that can remove most of the symptoms. I am a little skeptical of daosin, but will try that out as well. Thanks!