維他命B群 - 養生

前陣子托友人從美國帶回來GNC的維他命B群
吃了一陣子後發現
在吃過後頭往往會有種燥熱的感覺
而且有點暈暈的
提神的效果應該是有啦....
不過這種燥熱感又讓人有點卻步....
想請教一下
這樣子算正常嗎？
有任何可以改善的方法嗎？

--
You think you have a limit,and you better go for this limit and you touch this
limit, OK, this is the limit.
As soon you touch this limit, something happens to you; suddenly you can go
a little bit further.
With your mind power, your determination, your instinct and your experience
as well, you can fly very high.

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