Sinusitis is an infection of the sinuses, which are air-filled spaces in the bones of your face around the nose. Like the inside of your nose, the sinuses are lined with a thin layer of tissue called the mucous membrane that makes mucus (snot).
When you have a cold or allergies, the tiny holes that drain the sinuses can get blocked and trap mucus and germs in the sinuses, which can lead to sinusitis.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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