Is it permissible to chew gum while davening?*
*In the event that your mouth otherwise gets dry. The alternative would be taking periodic sips of water for medical purposes.
On Shabbos, carrying water into shul would be questionable and I doubt a rav would permit it. Even if it was allowed, taking a cup of water to one’s seat while davening is a recipe for a spill. Safety hazard.
The gum would lose flavor if it was fresh at the start of davening.
Would it be better to chew it enough first to lose the flavor, or would that require a separate Borei Nefashos while it’s still in the mouth?
So at this point the flavorless gum may be considered, by a non-halachic authority who wishes to plea one’s case, to be a medicine of sorts used to alleviate dry mouth.