Causes.

Acute Sinusitis

The most common causes of acute sinusitis are:

• Virus. Viral infections can paralyze or even destroy the cilia so that they are unable to move mucus out of the nose.

• Bacteria. If the sinus openings become blocked and the infected mucus cannot move out of the body or drain down the throat, it creates is an ideal environment for bacteria to grow. The bacteria in turn creates an acid environment in the sinuses, which further paralyzes the cilia. This causes the mucous membrane to swell more. The sinus openings become even more blocked.

• Fungus. Fungus is a plant or mold, often microscopic, that can be ingested with food or inhaled in the air. Once in the body, it can affect the immune system and aggravate the sinuses.

• Medications. The side effect of certain medications may affect the functioning of the mucous membrane

Cronic sinusitis is most often caused by:

• Allergies. Allergies can be caused by almost anything. However, the most common allergens are airborne particles, foods, animals, feathers, and fabrics. If the culprit is a food, fabric, or animal, simply avoiding the allergen will stop symptoms. If the allergen is a chemical or substance in the air, such as dust or ragweed, treatment such as regular allergy shots for a period of time can provide relief.

• Asthma. Adults and children suffering from asthma are more prone to sinusitis.

• Temperature and humidity. When temperature and humidity are extreme, or when these air conditions change quickly, the sinuses can become irritated.

• Defective mucous membrane. Some people have poorly functioning mucous membranes, sometimes permanently damaged by a past infection.