I'm very sensitive to supplements and try to be careful with initial doses. Based on the large doses that some people were taking with no ill effects, I thought 1g of piracetam with 450mg Alpha GPC choline would be safe to try.
Within an hour of taking this combination, I was seeing pixelation in my visual field, and about 8 hours into it, I felt like I was on Ecstasy, totally in love with the beauty of life and the richness of the moment. Not what I signed up for, but not a real problem so far. However...
Falling asleep that night I had a couple of discontinuities in my consciousness which felt like tiny seizures. I woke up the next day with many symptoms of acetylcholine overload - sore muscles, nausea, diarrhea, dizziness - and as the day went on, I had more symptoms - deep headache, vomiting, severe chills, sweating, stomach cramps. I took my temperature and it was normal, so I don't think I've had the flu. Almost 48 hours later I'm feeling mostly better, but only after taking some benadryl last night, which has anticholinergic effects. As the benadryl wears off, I'm noticing the headache, stomach pain and sore muscles coming back gradually.
After this happened, I noticed some other reports online of similar reactions, so I'm recording my experience here in hopes that people who know they are sensitive to supplements will be careful with this combination. These two compounds really potentiate each other. I took piracetam in the 1980s in dosages as high as 3g, and noticed almost no effect when taking it by itself.