When a cold lasts longer than seven to 10 days, or when symptoms seem to improve, then suddenly worsen, chances are good an acute sinus infection is the cause. The body can usually fight off infection if symptoms are mild.When symptoms last more than seven to 10 days, a secondary bacterial infection may be present. Antibiotics often can help.

The sinuses are a maze of air- filled chambers in the bones around the nose. They make mucus, which drains and moisturizes the nasal passages. When sinus openings become blocked due to the inflammation and swelling triggered by the cold virus, drainage is hindered and mucus builds. Bacteria thrive in this moist environment. A sinus infection can cause:

1. Nasal congestion and facial pain and pressure.

2. A thick yellow or greenish discharge that drains from the nose or down the back of the throat.

3. Headache, pain in the upper teeth and jaw, or ear pain that comes on abruptly, usually following a cold

Most cases of acute sinusitis come and go within a month. If symptoms linger, a physician may recommend tests to determine the cause and an appropriate treatment plan. The common cold isn't the only culprit that causes acute sinusitis. Other factors can include allergies, fungal infections, polyps in the nasal passage, and environmental pollution.

Testing might include nasal endoscopy, which involves inserting a thin, flexible scope with an attached light in the nose to visualize the drainage from the sinuses. This test helps identify abnormalities within the nose. Imaging tests of the sinuses or allergy skin testing also may be recommended.

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