Irrigation of sinuses with salt water solution twice day should help keep the mucous flushed out. I make a homemade solution of 1/2 teaspoon salt, 1/2 teaspoon baking soda, 1 cup boiling water, stir, strain thru paper coffee filter, fill clean nasal spray bottles. Let cool COMPLETELY. Hang head off bed while lying on back and squirt few sqirts in each nostirl. Turn head slowly side to side, get up slowly and you can say "kkkkkkk" while getting up to help keep solution from running down throat. Let drain minute or two and then blow. Later on you may find mucous releases and needs to be blown out. My doctor ok'd this, but you may wish to ask your doctor about it. This has served me well for many years. I also take Chlortrimton when allergy season is bad.
I am not a doctor.