The sniffling. The sneezing. The red, watery eyes. When our allergies act up and our sinuses get clogged, we often blame the great outdoors. But could the culprit actually be inside your own home? From dust mites to pet dander, there are countless allergens in the average household that can cause sinus pain and pressure.

"You can have an immaculately clean house and still have allergy problems," says Dr. D.J. Verret, a facial plastic surgeon at UT Southwestern Medical School. "There are dust mites on your blankets, on your bed linens, on your sofa, on pretty much everything."

Most of us are okay living with these allergens, but those who are sensitive to allergens usually end up running for the tissue box.

"When it comes to sinusitis, or sinus disease, what we've come to understand is that it's on a continuum with rhinitis or nasal allergies," says Verret. "Because the mucous of the lining of the nose also lines the sinuses, anything that irritates the nose will also irritate the sinuses and prevent them from working correctly."

The sinuses create mucous that should naturally drain, but if things aren't working correctly, they can get backed up. And that's when you start getting the pressure and the pain and the headaches.

If owners are allergic to their four-legged friends, pets can be an irritant. This can be the case even if a cat or dog resided in the home before they got there. Pet dander can get so ingrained in upholstery that you just have to remove everything of the previous owner's -- carpets, furniture, what have you -- and replace it to resolve the allergy problems, explains Verret. This time of year, air-conditioning systems can play a role in aggravating the ear, nose and ...