If you’re anything like 37 million other Americans, you may be suffering from sinus irritations around this time of year. Sinuses are the internal hollow spaces behind the eyebrows, in the cheekbones, behind the nose, and between the eyes. The function of sinuses is to condition inhaled air with mucous and other natural secretions before it reaches your lungs. Acute sinus irritations, which are usually caused by viral respiratory infections, go away after a week or two on their own or after treatment with antibiotics or decongestants.