A bacterial sinus infection is a condition in which the sinuses—mucus membrane-lined cavities inside the head—are inflamed and blocked with mucus or pus. A sinus infection can cause symptoms like a headache or green nasal drainage. It can also mimic a cold that does not improve or go away after more than a week. There are three main types of bacterial sinus infection: acute, subacute, and chronic, and the length of a sinus infection is one major factor in diagnosing its type. Treatment for a sinus infection traditionally includes medication and a humidifier, and surgery is occasionally required to correct the problem.
A seasonal allergy attack or a bout with the common cold virus often precedes a sinus infection. When nasal secretions cannot drain out of the sinus cavities, and a buildup of mucus occurs, the nasal passages become an ideal breeding ground for bacteria. A few other possible causes of a sinus infection include a foreign body inserted in the nose, medication that impairs the mucus membranes, and infection from the root of a diseased tooth.
When bacteria invade the sinuses it can cause a "stuffy nose" feeling, pain or pressure in the eyes and the mouth, and headaches. Sinus infection drainage is often thick and green or yellow, and might be tinged with blood. An earache, fever, or sore throat can also accompany a bacterial sinus infection. Swallowing the infected drainage can cause an upset stomach, and it is not unusual to experience a sinus infection and nausea.
The length of a bacterial sinus infection can be instrumental in determining the type. An acute infection is one that has been present for about a month or less. Subacute infections are likely to stretch from a month to around ten weeks. Diagnosis of chronic sinusitis is made when the infection continues to be present after a period of approximately ten weeks. Chronic sinusitis can also refer to a condition where the bacterial infections occur often and repeatedly.
Treatment for a sinus infection varies depending on the type and cause. A fungal sinus infection is frequently treated with a steroid nasal spray, while antibiotics are commonly indicated for a bacterial sinus infection. Antihistamines and decongestants can be used sparingly and with caution, and a humidifier might help relieve discomfort and thin the infected mucus. In some cases, surgery might be required to improve nasal drainage and relieve a chronic sinus infection.