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  • Definition

    sinusitis is an inflammation of the nasal sinuses. It is usually caused by infection (bacterial or viral), but can also be caused by allergic reactions or other responses to environmental agents.


    The sinuses are holes in the skull between the facial bones. There are four large sinuses: two inside the cheekbones (the maxillary sinuses) and two above the eyes (the frontal sinuses).

    There are also smaller sinuses (ethmoidal and sphenoidal sinuses) located between the larger ones. The sinuses are lined with membranes that secrete antibody-containing mucus, which protects the respiratory passages from the onslaught of irritants in the air we breathe.


    Most sinusitis is caused by infection (such as a cold or an upper respiratory tract infection) spreading to the sinuses from the nose along the narrow passages that drain mucus from the sinuses into the nose.

    allergies to dust, pollen, pet dander; indoor air pollutants, such as cigarette smoke, rug shampoo and formaldehyde (used in the manufacture of carpeting, particleboard and plywood); and outdoor air pollutants all can induce inflammation.

    Excessive dryness in homes and offices from dry-air heating and air-conditioning systems can also inflame the sinuses.

    Immunologic, as well as structural problems, such as narrow drainage passages, nasal obstruction (tumors, polyps or a deviated septum) problems are other possible causes of sinusitis.


    The classic symptoms of chronic (long lasting) sinusitis are:

    • a dull ache or pressure across the midface, especially between or deep into the eyes
    • a headache that occurs daily for weeks at a time, and is often notably worse in the morning and with head movement
    • nasal congestion
    • postnasal drip

    The classic symptoms of acute (short lasting) sinusitis are:

    • fever
    • nasal obstruction
    • raspy voice
    • pus-like (purulent) nasal discharge
    • loss of sense of smell
    • facial pain or headache that is sometimes aggravated by bending over (When pain is present, this may suggest which sinus is affected.)

      Maxillary sinusitis (the most common type) manifests as cheek or dental pain. Forehead pain indicates frontal sinusitis. Pain at the bridge of the nose or behind the eye suggests ethmoid sinusitis. Pain is often referred to the top of the head with sphenoidal involvement.

    Less common signs of sinusitis include:


    The doctor will examine the mouth and throat and look up the nasal passages to determine whether the sinus outlets are blocked. Additionally, the doctor may do a transillumintion or a cat scan.

    transillumination is done in a dark room with a very bright flashlight that is pressed against the forehead or cheek. If the light shines through the sinuses, the doctor can rule out sinusitis. If little or no light penetrates, the cavity is clogged and sinusitis is evident.

    CAT scan is a diagnostic technique in which the combined use of a computer and x-rays are passed through the body at different angles, producing clear, cross-sectional images of the nasal cavities.

    The doctor may also perform an endoscopic examination. This is a narrow, flexible fiber-optic scope that is placed into the nasal cavity through the nostrils. It allows the doctor to view where the sinuses and middle ear drain into the nose.

    Predisposing factors in the patient's history may help confirm the diagnosis or indicate underlying conditions that require therapy. The two most common predisposing factors are a recent upper respiratory tract viral infection (lasting more that seven to 10 days) and allergic disease.

    Additionally, sinusitis is especially likely if cold symptoms are unusually severe or accompanied by a high fever, pus-like nasal discharge or puffy eyes.


    If a bacterial infection is present, antibiotics, such as amoxicillin, erythromycin or sulfa drugs, are usually prescribed for about 10 days.

    Your doctor also may prescribe one or more of the following remedies (which can be useful in reducing inflammation in the sinuses and nose and speeding recovery):

    • Decongestants. These temporarily relieve symptoms and also help the healing process by draining the nose and sinuses.

      Decongestants like pseudoephedrine, phenylpherine and phenylpropanolamine constrict the blood vessels and shrink the sinus and nasal membranes, thus, reducing stuffiness in the sinuses and nasal passageways.

    • Over-the-Counter Nasal Sprays. These products, including Afrin and Dristan, are decongestants in a spray form. They are effective when used for a few days, but can be addicting when used for longer periods of time.

      After using decongestant sprays for three days, people usually experience a rebound effect - when they stop using the spray, they become even more congested and need more spray for relief. People with chronic allergies or sinus problems should limit the use of decongestant sprays to five treatments a week.

    • Prescription inhalers. Several types of prescription nasal inhalers can help reduce sinus inflammation (these are not decongestants and are not habit-forming). Prescription inhalers help heal sinus membranes after the bacteria have been eliminated. These drugs include Beconase, Nasalide and Vancenase (all cortisone derivatives) and Nasalcrom (a non-cortisone drug).

      When used as directed by a doctor, prescription inhalers can be taken safely for months.

    • Expectorants. Medicines, such as Guaifenesin, thin the mucus so it drains more easily.
    • Antihistamines. These medications help relieve nasal itchiness and inflammation by blocking the action of histamine, however, they do not help mucus drain. Antihistamines include chlorpheniramine, Hismanal, Seldane and Tavist.
    • Humidifiers and salt-water sprays. Dry-air heating systems and air-conditioning can cause sinus membranes to dry out, crack and become vulnerable to irritants, inflammation and infection. Keeping a humidifier running in your home and office or using an over-the-counter salt-water spray (inhaled through the nose) five or six times a day can provide dramatic relief.

    Recurring sinusitis accompanied by a bacterial infection usually requires one of the new, stronger antibiotics, such as Augmentin, Ceclor or Ceftin. These drugs may be given in larger doses for a longer period of time (up to four weeks) than required for a brief bout of sinusitis. The doctor may also recommend continued use of a prescription nasal inhaler for several months to keep the inflammation down and prevent a recurrence.


    Are any tests needed to diagnose the condition or determine the cause?

    Is the sinusitis caused from allergies or a bacterial infection?

    Will you be prescribing any medications? What are the side effects?

    How effective is the medication?

    How long will it take to feel relief of pain and discomfort?

    If you are recommending nasal sprays or medication, which ones are most effective?

    Are there any home treatments you might recommend?

    • Reduce exposure to allergens.
    • Improve household ventilation by opening windows whenever possible.
    • Use a humidifier in the home or office when the person has a cold.
    • Sleep with the head of the bed elevated. This promotes sinus drainage.
    • Use decongestants with caution.
    • Avoid air pollutants (such as smoke) that irritate the nose.
    • Eat a balanced diet and exercise.
    • Minimize exposure to persons with known infections.