Get a Neti Pot.  My wife saw it on the Dr. Oz show and got one for herself.  It stopped her sinus headaches and pressure.  I thought that looked gross and would never do it.  Well after my sinus medicine quit working I gave it a try.  Couldn't believe how well it worked. Do it 3 or 4 times a day when you are having problems and  once or twice when your not.  Walmart or Walgreens has them for under $20.  Here is a link to one similar to what I have.   After the salt mix runs out just buy some sea salt at the grocery store and use that.