Antihistamines are the medications used most frequentlyto treat allergic rhinitis. They are useful in treating rhinorrhea, sneezing, nasal itching, and ocular itching but are lesshelpful in treating nasal congestion. First-generation antihistamines, such as diphenhydramine and hydroxyzine, easily cross the blood-brain barrier, with sedation as the mostcommon reported adverse effect. Use of first-generation antihistamines in children has an adverse effect on cognitive andacademic function. In very young children, a paradoxicalstimulatory central nervous system effect, resulting in irritability and restlessness, has been noted. Other adverse effectsof first-generation antihistamines include anticholinergiceffects, such as blurred vision, urinary retention, dry mouth,tachycardia, and constipation. Second-generation antihistamines, such as cetirizine, loratadine, desloratadine, fexofenadine and levocetirizine, are less likely to cross the blood-brainbarrier, resulting in less sedation. Cetirizine, fexofenadine,and loratadine are over-the-counter medications. Azelastine and olopatadine, topical nasal antihistamine sprays,are approved for children older than 5 years and older than6 years, respectively.
Decongestants, taken orally or intranasally, may be used to relieve nasal congestion. Oral medications, such as pseudoephedrine and phenylephrine, are available either alone or in combination with antihistamines. Adverse effects of oral decongestants include insomnia, nervousness, irritability, tachycardia, tremors, and palpitations. For older children participating in sports, oral decongestant use may be restricted. Topical nasal decongestant sprays are effective for immediate relief of nasal obstruction but should be used for less than 5 to 7 days to prevent rebound nasal congestion (rhinitis medicamentosa).
Topical ipratropium bromide, an anticholinergic nasalspray, is used primarily for nonallergic rhinitis and rhinitis associated with viral upper respiratory infection. Leukotrienemodifiers have been studied in the treatment of allergic rhinitis. Montelukast is approved for use in seasonal allergicrhinitis.
If environmental control measures and medication intervention are only partially effective or produce unacceptable adverse effects, immunotherapy may be recommended. The mechanism of action for allergen immunotherapy is complex but includes increased production of an IgG-blocking antibody, decreased production of specific IgE, and alteration of cytokine expression produced in response to an allergen challenge. Immunotherapy is effective for desensitization to pollens, dust mites, and cat and dog proteins. Use in young children may be limited by the need for frequent injections. Immunotherapy must be administered in a physician’s office with 20 to 30 minutes of observation after the allergen injection. Anaphylaxis may occur, and the physician must be experienced in the treatment of these severe adverse allergic reactions.
Approximately 60% of children with allergic rhinitis have symptoms of reactive airways disease/asthma (see Chapter 78). Chronic allergic inflammation leads to chronic cough from postnasal drip; eustachian tube dysfunction and otitis media; sinusitis; and tonsillar and adenoid hypertrophy, which may lead to obstructive sleep apnea. Children with allergic rhinitis may experience sleep disturbances, limitations of activity, irritability, and mood and cognitive disorders that adversely affect their performance at school and their sense of well-being.
Seasonal allergic rhinitis is a common and prominent condition that may not improve as children grow older. Patients become more adept at self-management. Perennial allergic rhinitis improves with allergen control of indoor allergens.