Have you ever used a Neti​ Pot? I use it all the time to clean out my sinuses.  I actually heard about it from some of my former yoga students. The first time you try it, it is a little strange, but once you get used to it can feel like such a relief!  It is a glass or plastic container, that kind of looks like something you would rub and a genie would pop out.  You can get them at any local pharmacy in plastic or glass.  The salt is sold in either packets or in a Ziplock bag and contains no preservatives.  Sometimes I use it a few times a week, other times it can be a month before I use it again.