My Mom has them every few years and I know other people who have had them and know of NO ONE who has even felt n from it. Apparently the "cleaning out" isn't fun but doesn't make you n or v. Also as has been said ask for anti emetics, most doctors are pretty understanding. Its best to be safe and have the colonoscopy done.
\"As soon as you trust yourself,you will know how to live.\"
Johann Wolfgang von Goethe
\"Do not anticipate trouble, or worry about what may never happen. Keep in the sunlight.\"
Benjamin Franklin