By Amy Heneghan, M.D.

Sneezing, runny nose, watery eyes and fatigue may look like symptoms of the common cold, but for many children, these symptoms are caused by allergies. Inflammation and irritation of the nasal passages due to seasonal and year-round allergens is called allergic rhinitis, and it is one of the most common illnesses in the United States, affecting one in three people.

Allergic rhinitis can develop at any age and affect children as young as 4 months. This common health problem tends to run in families, can last for life and can lead to many days of missed school or work. It also can affect a child’s quality of life just like any other chronic illness. In fact, some consider it the most common chronic disease in children.

Symptoms of allergic rhinitis include sneezing, runny nose (rhinorrhea), nasal congestion, itchy nose and post-nasal drip. Some people with allergic rhinitis also may suffer from wheezing, eye tearing, sore throat and chronic cough. In addition, sinus headaches and “plugged” ears are common problems.

Symptoms can be mild or severe, depending on the time of year and the type and frequency of exposure to the substance that is triggering the allergic reaction. Uncontrolled symptoms also can lead to other problems, such as sinus infections, ear infections, more frequent cold viruses, nosebleeds and worsening of asthma.

What causes allergic rhinitis?

Allergic rhinitis typically is caused by tiny particles in the air that the body’s immune system mistakes for a threatening substance. Tree, grass and ragweed pollens are the most common seasonal outdoor allergens. Spring is an especially difficult time for children with seasonal allergies because that is when plants reproduce and the amount of pollen in the air is highest. Dust mites, cockroaches, molds and animal dander are examples of indoor allergens that can lead to symptoms all year long (perennial allergies).

How is allergic rhinitis diagnosed?

Because allergic rhinitis can cause symptoms that are very similar to an upper respiratory infection (a cold), a careful history and physical exam by your child’s doctor is needed to diagnose the condition. The doctor will look for the following clues:

• Patterns in when and where symptoms worsen. Allergic rhinitis is more likely in children who have symptoms associated with a season or a known trigger, such as cat dander.
  
• Other allergic diseases. The presence of other known hereditary allergic diseases, such as eczema, or a family history of allergies is more common in children with allergic rhinitis.
  
• Physical signs of allergies that look slightly different from the signs of a common cold. These often include swollen and pale nasal mucosa (lining of the nose), red eyes, swelling of the eyelids and “allergic shiners” (darkened areas under the lower eyelids). Itching of the eyes or nose also is a common feature of allergies that is usually not seen with a cold. In addition, the common cold symptoms of fever and sore throat are absent with allergies.
  
• Skin testing, which involves injecting a small amount of the suspected allergen under the skin and watching for a reaction, is the most definitive way to confirm the diagnosis of allergic rhinitis. However, this test may be unreliable for children under age 2.

How is allergic rhinitis treated?

The goal of treatment is to reduce allergy symptoms. Avoiding the allergen is the best treatment, but certain medications also can help. Here are some tips for treating allergic rhinitis:

• Seasonal allergens and pollens are difficult to avoid outdoors, but you can minimize their effects indoors by closing windows and running air conditioners.
  
• You can reduce exposure to year-round (perennial) allergens, such as dust mites and molds, by covering pillows and mattresses with plastic covers and removing dust-collecting household items, such as carpets, heavy drapes and bedspreads.
  
• Although air purifiers and dust filters can be costly, they may help reduce the amount of an allergen in the air.
  
• Saline nasal sprays and humidity can help congestion and are very low-risk treatments.
  
• Allergic rhinitis is caused by the immune system triggering the body to produce inflammation with chemical agents called histamines. Therefore, antihistamines, such as Benadryl (chlorphenhydrmine), can reduce symptoms by blocking the histamine cycle of allergies. Non-sedating (less likely to cause drowsiness) and long-acting antihistamines, such as Claritin (loratidine) and Zyrtec (fexofenadine), are widely used and available over the counter in both tablet and liquid forms. The U.S. Food and Drug Administration (FDA) has approved Zyrtec for use in children as young as 6 months. Talk with your doctor about which of the several prescription antihistamines on the market your child should take.
  
• Nasal sprays such as Nasalcrom (cromolyn sodium) or steroids such as Flonase (fluticasone) and Nasonex (mometasone furoate monohydrate) work extremely well for nasal symptoms. However, young children often do not tolerate these drugs well and the drugs may take up to two weeks to work.
  
• Allergy shots (immunotherapy) involve injecting a child with gradually increasing doses of the substance that triggers the allergic reaction. The shots help the immune system produce an antibody to block the substance that triggers the allergy. This reduces the symptoms of the allergy when that substance is encountered in the future. Maintenance injections are usually given once every three to four weeks. Although almost 90 percent of patients have improved symptoms with allergy shots, the shots are not a cure for allergic rhinitis and are usually given only to children whose symptoms did not improve with other therapies.

What should I ask my child’s doctor about allergic rhinitis?

• What type of medical treatment is best for my child?
  
• What over-the-counter medications are most effective? What are the medications’ side effects?
  
• Do you recommend skin testing to diagnose allergic rhinitis or to pinpoint the responsible allergens?

Dr. Heneghan is a pediatrician at PAMF's Palo Alto Center.