Is It Safe To Chew Nicorette Gum Prior To Gastrointestinal Check Up?

What happens if I swallow a piece of nicorette gum twice in one week? Also I am having an upper GI tommorow for celiacs disease and have been told no food nor drinks after midnight, can I still chew nicorette or chew at least regular sugar free gum? Or will this affect my testing. I quit smoking cigarettes 2 years ago but am still addicted to nicorette.