At least, I suspect it is the choline as I have had the same reactions taking choline on its own.
This is how it happens: I pop a Vimmortal (even just 1 tablet will do), and 30-60 minutes later my temples start feeling tender, I can feel shoots of pain going up the back of my neck, and I feel the onset of a pretty awful headache. This is surprising as I would have thought that 1/6th of a 550mg dose of choline would be benign, but apparently it's enough to cause this same reaction. I've now replicated this on 5 separate occasions at different times of day. It's unfortunate, as I now have a bottle with 174 of 180 tablets here that will probably go to waste.
Edited by beatsme, 26 November 2010 - 02:17 AM.