May not be the correct answer for you, but it's true for me. In the winter when the temperature has dropped suddenly I often need to take a decongestant for a few days and then I'm fine for the rest of it. Crud in your sinuses (for me at least) caused by allergies (grasses in my case) or weather can trigger a low-grade fever and other cold-like symptoms. It's worse since I work in a heated (too hot, IMO) office and then have to go back out into the cold. This was less of a problem when I worked in a more "frugal" office where the temperature (while still warmer inside) wasn't so extremely different from outside.
May not be the correct answer for you, but it's true for me. In the winter when the temperature has dropped suddenly I often need to take a decongestant for a few days and then I'm fine for the rest of it. Crud in your sinuses (for me at least) caused by allergies (grasses in my case) or weather can trigger a low-grade fever and other cold-like symptoms. It's worse since I work in a heated (too hot, IMO) office and then have to go back out into the cold. This was less of a problem when I worked in a more "frugal" office where the temperature (while still warmer inside) wasn't so extremely different from outside.