medicine for thick mucus in throatthick mucus buildup in throatexcess thick mucus in throatthick mucus stuck in back of throatfrequent mucus in throatoverproduction of mucus in throatmucus in throat constantlymucus in throat allergiesreason for mucus in throatmucus buildup in throatmucus stuck in back of throatwhite mucus in back of throat