Hi welcome to H.C.M.Forum. snoring
in children is mainly due to under developed epiglttis. other reason is adenoides as your doctor said. carton he gave for 5days only . montene recomended dose is for 3months. decided concerning all the factors in mind. they will consider the benifit againest side effects. inthis case montene is not that much necessory, so if you want you can stop after few days.
food restrictions.avoid coolwater, cooldrinks , icecreams. etc for few days. don't worry he will be fine.