What affects does too much vitamin C have?

around 200% daily recommended...

you pee it out- the body just won't absorb what it doesn't need

RDA for females is around 75mg.  150mg won't hurt you.   (whoops - you're a guy     90mg for men.)

See Merck for more info.

I take roughly 7,000 to 10,000 mg of vitamin C daily. The only things that might happen are tummy cramps or loose stools... otherwise, nothing. It is a water-soluble vitamin which means you pee it out. 

Ditto to other posters. Too much C can give you the runs, but only at like 15x or more of the daily reccommended intake, or something crazy like that. I take a C supplement that gives me 833% DV and have no digestion issues.

Too much Vitamin C might also cause nausea.