★★★★★
One thing I found helps lessen the pain is the "nose bullets" as I call them. Tubes you stick in your nose and inhale the vapors. They contain Camphor/Menthol. They do not "cure" a sinus headache, but lessen the pain. Heating up some "chest rub" in a jar does the same, but it is not as portable. Also, rubbing the "chest rub" onto your forehead helps soften the pain. I use Neti pots but add 1 teaspoon or less of Xylitol and several drops of hydrogen peroxide per each pot full to the standard salt/baking soda powder that is out there.
I post these not as medical advise, but something that has worked for me to make living with sinuses more bearable.