Although I didn't mention it, I was already taking 500 mg of a "no Flush niacin", which caused absolutely no flushing at all. What prompted me to investigate further was paying closer attention to the ingredients. It wasn't niacin at all, but something with a long name and the word "inositol" in it. Further research showed it wasn't as effective as real niacin, or nicotinic acid. So, I already had the number 500 in my mind. Still, taking that large dosage was a dumb thing to do, without first starting out slowly and gradually building up.