I just realized that must be what's happening to me. Haven't slept for a week (insomnia and when I finally fall asleep I wake up). First I thought it was D-ribose but then I stopped it and continued raising folate (folic acid) and just woke up: 3 AM, sweating and feeling all flushed. Heart beating too fast, but part of it could be due to doing too much. I've gone from 3 mg of folate to 6 mg the last week. And took a shot of methyl B12 last Sunday, then Wednesday, Sunday and Tuesday. I got great energy after three years of experiencing no effect at all from B12. I used to have great effect. Seems it's working but too much too quickly? Getting niacin tomorrow. Got all the advice I needed from another thread and from chatting. Thanks PR!