EurekAlert! -- Facial pain. Nasal congestion. Postnasal drip. Fatigue. These are hallmark signs of chronic sinusitis, a swelling of tissue in the nasal and sinus cavity. The illness strikes millions of Americans each year and is one of the top five reasons patients visit their primary care doctor. Treating sinusitis is difficult in part because it's often not known if the cause is viral or bacterial.
