 This study, in subjects with FGIDs, is a , randomized, sham-controlled, single-centre pilot investigation designed to compare two parallel groups, gammaCore-G active treatment and a sham, inactive treatment. The study period will begin with a two-week run-in period, followed by a four week comparative period when the subjects will randomized 1:1 to either active treatment or sham inactive treatment. The comparative period will be followed by an open label four week period, where the subjects in the sham treatment group will switch in treatment assignment to receive active treatment and the active group will continue to receive an active treatment. 