I have suffered from sinus allergies on and off since I was ten. I am the only one in my family with the problem even though we ate the same diet. Blood test about 15 years ago showed that I am very allergic to dust mites and the allergy shots worked. The problem is now my insurance won't go for it unless I tried nasal steroid sprays like Rhinocort first, which by the way works well. I have been able to keep my sinus allergy at bay most of the time I think through eating a good diet and only use the rhinocort sparingly when I need it maybe once a month. Three times over the last four years my sinus got completely blocked and could only breath through my mouth which causes sleep apnea from dried throat tissue. It happened again last week following a head cold and all three times I had to go on steroid like prednisolone and methylprednisolone which open my sinus the first day I use it. They work extremely well but can have serious side effects and that's why the prescription is for one month or six days at a higher dosage. I noticed that when my thryoid is underactive I get more congested too. Now, I noticed that the only three times that my sinus got completely blocked and had to go on prednisolone steroid was after I had been doing a nasal salt water rinse with the neti pot and/or Grossan hydro pulse. I only have come across one person on the net say that rinsing your sinus with salt water can make it worse, everybody else swears by it and even my doctors have told me to try it. Could it be that in my case the salt water causes or makes the sinus inflammation worse? After it happen everytime I did the nasal salt water irrigation I am believing now that that's what blocked my sinus completely. If I can get a confirmation I will then smash the neti pot and hydro pulse with a hammer. You probably know more than anyone else how salt water can affect your nasal membrane.