I started taking vitamin c a week ago and three days ago I stArted to get these itchy bumps on arm first then legs now neck I just want to itch them off

I started taking vitamin c a week ago and three days ago I stArted to get these itchy bumps on arm first then legs now neck I just want to itch them off

I suspect it's an allergy to SOMETHING in the produce you are taking.

Obviousy - stop taking it and see what happens.