blocked saliva gland by tongue and gum

[Mexican cuties]

hi just noticed our little man has a pea size lump between the side of his tongue and gum, vet has given us antibiotics to start with, as they suspect blocked saliva gland, any idea how effective this will be before we have to put him in for surgery?? never had this before in any of our other dogs??

he is still eating, acting normal and happy in himself as well.