Allergic Rhinitis: A Review of Therapeutic Choices

ABSTRACT: Allergen avoidance measures are the first course of action in the treatment of allergic rhinitis in children. Of the many pharmacological options for allergic rhinitis, second-generation oral or intranasal antihistamines remain the mainstay of treatment for mild intermittent symptoms. Intranasal corticosteroids are the most effective medications for moderate to severe symptoms. In patients who do not respond to pharmacotherapy, allergen immunotherapy may be effective. Immunotherapy can change the clinical course of allergic disease by reducing the risk of new allergic sensitizations and by preventing the progression of allergic upper airway disease to lower airway disease, such as asthma. To be successful, this lengthy treatment requires family commitment to patient adherence.
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Allergic rhinitis is a common chronic condition in children that causes substantial morbidity and results in billions of dollars in health care costs and millions of lost school days each year. Although it is not life-threatening, poorly managed allergic rhinitis has several potential, long-term consequences in children. These include increased bronchial hyperactivity,¹ chronic otitis media with effusion,² bacterial sinusitis,³ adenoidal hypertrophy,⁴ and dental and skeletal maldevelopment.⁵ With the prevalence of allergic rhinitis increasing worldwide, there is a  compelling need for pediatric practitioners to be able to recognize allergic disease and provide optimal treatments for affected children.

In this article, I review the 3 approaches to the management of allergic rhinitis: allergen avoidance, pharmacotherapy and immunotherapy. A combined approach using allergen avoidance and pharmacotherapy can usually prevent progression of the IgE-mediated inflammatory process and improve the patient’s quality of life. In a previous article (CONSULTANT FOR PEDIATRICIANS, May 2012, page 129), I addressed issues related to the diagnosis of allergic rhinitis in children.

ALLERGEN AVOIDANCE

The first course of action in the treatment of allergic rhinitis is the reduction of offending allergens in the home. Home environmental control should be stressed to families of allergic children when sensitization first occurs.⁶ When discussing avoidance strategies with parents, clinicians should bear in mind potential limitations. The child’s housing situation, for instance, may limit the ability to control allergens (eg, rental properties that prohibit interior alterations, such as carpet removal).

House dust mites and indoor molds. Measures to control house dust mites and indoor molds include enclosing the mattress, box spring, and pillows in allergen-proof casings; washing bed linens and stuffed animals weekly in hot water; reducing indoor humidity to 50% to 60% using an air conditioner or dehumidifier; replacing carpet with hardwood flooring, when possible; and frequent vacuuming. Use of high-quality air filters in heating/air-conditioning units, vacuums, and vent outlets and use of a portable air-cleaner unit with a high-efficiency particulate arresting  (HEPA) filter in children’s bedrooms have been advocated.^7-9

Pollens and outdoor molds. To reduce exposure to pollens and outdoor molds, the family can bathe the child or have the child take a shower on entering the house before reaching the bedroom, change the child’s clothing daily, keep windows closed during pollen seasons, and keep the child away from lawns being mowed. Families may consider limiting outdoor activities during the pollen seasons.

Pet dander. Pet allergens are best avoided by removing the pet. When this is not possible, the family can prevent the pet from entering the child’s bedroom, bathe the animal biweekly, and use an air-cleaner with a HEPA filter.

Food. For children with a known food allergy, the offending food can be replaced with an adequate substitute to support the child’s nutritional requirements. Many children outgrow early food sensitivity especially milk and egg allergies. However, allergies to peanuts, tree nuts, and shellfish are more persistent so that regular follow-up of children with these allergies should be encouraged.

PHARMACOTHERAPY

Antihistamines. Second-generation oral antihistamines (cetirizine, loratadine, fexofenadine, desloratadine, levocetirizine) continue to be the mainstay of treatment for allergic rhinitis, especially for mild intermittent symptoms (Table). Oral antihistamines reduce symptoms of rhinorrhea, pruritus, and sneezing, as well as the watery eyes frequently associated with rhinitis. However, they have little objective effect on nasal congestion, runny nose, and postnasal drainage, and they have not been proven useful for nonallergic rhinitis.

The second-generation antihistamines have a rapid onset of action and do not cross the blood-brain barrier, which results in minimal anticholinergic activity and less drowsiness. This is in contrast to first-generation antihistamines, which have been associated with impaired learning and school performance in children. The second-generation antihistamines can be used as needed for rhinitis symptoms, but they generally are more effective with continuous use.¹⁰ Oral suspensions are available and ease administration and compliance in young children. Fexofenadine oral suspension has been shown to be effective and well-tolerated in children as young as 2 years.¹¹

The intranasal antihistamines (azelastine and olopatadine) are also safe and effective treatment of perennial allergic rhinitis in older children (see Table).^12,13 However, the nasal spray has to be used twice a day and has a bitter taste, which are drawbacks for use in younger children. Combining intranasal antihistamine with an oral antihistamine is not recommended because it could increase the risk of side effects, mainly drowsiness.

Intranasal corticosteroids. Intranasal corticosteroids are the most potent drugs for allergic rhinitis, both seasonal and perennial, in children. They can relieve all symptoms of allergic inflammation and are highly recommended for moderate to severe cases. They are also effective for nonallergic rhinitis. Because of their short half-lives and rapid first-pass hepatic metabolism, they have limited systemic effects, although the onset of action is slow. The wealth of the available clinical evidence suggests that use of intranasal corticosteroids at the recommended dosages is safe in children with allergic rhinitis and does not significantly affect growth. Nevertheless, growth should be monitored regularly in children receiving intranasal corticosteroids.¹⁴

In children, the dose of an intranasal corticosteroid is usually limited to 1 spray in each nostril. To maximize the drug’s effect, children can be taught to synchronize with a deep inhalation when the medicine is sprayed into the nostril. It is ideal if children can hold their breath for 6 seconds to help spread the medicine on the nasal surface.

Decongestants. The oral decongestants pseudoephedrine and phenylephrine are sometimes used in combination with antihistamines (such as the fixed combination of cetirizine with pseudoephedrine). These combinations may alleviate congestion caused by both allergic and nonallergic rhinitis but have adverse systemic effects, which should be explained to the patient or parents. However, the FDA has issued a warning that the effectiveness of many products marketed as cold or allergy drugs has not been proven. Therefore, they should not be given to children younger than 2 years.¹⁵ For use of over-the-counter (OTC) cough-and-cold medicines in children aged 2 years and older, the FDA has recommended that parents check the active ingredients of the medication, be extra cautious when giving more than one OTC medicine to a child, follow the directions carefully, and use only the measuring spoons or cups that come with the medicine or those made specifically for measuring drugs.

Decongestant nasal sprays, such as oxymetazoline, decrease nasal congestion, although they do not substantially affect itching, sneezing, and rhinorrhea. They have a more rapid onset of action than oral decongestants. Prolonged use (eg, continuous use for 3 or more days) can lead to rebound congestion (rhinitis medicamentosa). If this complication develops, therapy with intranasal decongestants is usually suspended for 1 to 2 months. During that time, patients may use an intranasal antihistamine. Patients taking an intranasal decongestant should have their blood pressure checked and report any instances of headache, difficulties in sleeping, or jitteriness.

Other agents. Another option for treating children with allergic rhinitis is the leukotriene receptor antagonist montelukast. Many children prefer an oral medication to a nasal spray, and this drug is generally well-tolerated in children. Its efficacy in the treatment of allergic rhinitis is similar to that of oral antihistamines. A few studies suggest a beneficial effect when montelukast is combined with an oral antihistamine, but this combination appears less effective than single-agent use of an intranasal corticosteroid.¹⁶ The expense of montelukast can be a concern with regular use.¹⁷

Cromolyn, a mast cell stabilizer available as a nasal spray, is particularly useful for preventing rhinorrhea, pruritus, and sneezing of seasonal allergic rhinitis when used before allergen exposure. It is generally safe, which permits its use in young children. However, the need for prophylactic application and frequent administration because of its brief duration of action may result in poor compliance.

Ipratropium nasal spray, an anticholinergic agent, is most beneficial in patients whose most prominent symptom is clear anterior rhinorrhea, such as those with gustatory rhinitis.

Another treatment option is the use of a nasal wash with nonmedicated saline to flush out inhaled allergen particles that are trapped or clogged in the nasal tract. This method “makes sense,” appears to be safe, and may be considered in older children (12 years and up) with allergic rhinitis after outdoor activities. However, the effectiveness of this method remains to be demonstrated.

IMMUNOTHERAPY

Children with severe allergic rhinitis who have not responded well to one or more of the treatments described above may benefit from referral to an allergist who can offer the patient and family the option of allergy testing. Testing to identify the offending allergen may then help to guide the most appropriate treatment.

One final treatment option may be allergen immunotherapy. This treatment involves the administration of allergen extracts to achieve clinical tolerance of those allergens that cause symptoms in patients with allergic conditions. It is indicated for children with allergic rhinoconjunctivitis and severe anaphylactic reaction to Hymenoptera stings and should be considered in children with asthma and/or allergic rhinitis.^18,19 It has been shown to be effective in patients with mild forms of allergic disease and in those who do not respond to pharmacotherapy.¹⁹ Most immunotherapy is given by subcutaneous injection; however, the sublingual route is another option that is currently under study.

Immunotherapy can change the clinical course of allergic disease by reducing the risk of new allergic sensitizations and by preventing the progression of allergic upper airway disease to lower airway disease, such as asthma. Studies have demonstrated the efficacy of immunotherapy in preventing the development of asthma in patients with rhinitis.^20,21 The duration of immunotherapy varies from 3 to 5 years; however, the benefits are usually sustained for years afterward. Before embarking on such lengthy therapy, parents and patients should be well informed about its benefits and potential side effects. One study demonstrated the potential for early and significant cost savings in children with allergic rhinitis treated with immunotherapy.²² However, this cost savings depends on patient adherence; thus families need to be committed to the treatment for it to be successful.