Began vomiting after eating guacamole at a family gathering. 1 other person also became ill. day 2 i have developed bad diarrhea. can i take questran (cholestyramine)?

No- see your doc...: Food poisoning / GI infections from food typically results in a defense mechanism in your body of evacuation ( you are literally trying to get the "stuff" out of your body). Cholestyramine essentially slows the progession of feces through your system; if there is infection, you are extending its presence. This medication is not recommended until you are sure you don't have an infection.