Hello and welcome.
Gaviscon + Viscous Xylocaine is an old cocktail we used to give to the patients in the ER to treat heartburn or epigastric pain. To the best of my knowledge it never treated nausea.
May I suggest that you see a GI specialist as you were dx with GERD in 2004, going on 6 years ago.
You are sure to hear from other members re you concerns.