• Allergic rhinitis: Inflammation of the nasal membranes and is characterized by a

symptom complex that consists of any combination of sneezing, nasal congestion,

conjunctival, nasal and pharyngeal itching, and lacrimation (rhinorrhea) all occurring in a temporal relationship to the allergen exposure.

• Rhinitis is present as sneezing attacks, nasal discharge, or blockage occur for more than an hour on most days.

A limited period of the year (seasonal rhinitis-often called hay fever)

Throughout the whole year (perennial rhinitis)


Epidemiology of Allergic Rhinitis

• Allergic rhinitis occurs in persons of all races.

• Prevalence of allergic rhinitis seems to vary among different populations and cultures,

which may be due to genetic differences, geographic factors, or environmental

differences, or other population-based factors.

• Worldwide, prevalence rates vary from 2%-20%

Sex

• In childhood, allergic rhinitis is more common in boys than in girls, but in adulthood, the

prevalence is approximately equal between men and women.

Age

• Onset of allergic rhinitis is common in childhood, adolescence, and early adult years, with

mean age of onset 8-11 years, but allergic rhinitis may occur in persons of any age.

• In 80% of cases, allergic rhinitis develops by age 20 years.

• Allergic rhinitis often coexists with other disorders, such as asthma, and maybe

associated with asthma exacerbations.

• Allergic rhinitis is also associated with otitis media, eustachian tube dysfunction,

sinusitis, nasal polyps, allergic conjunctivitis, and atopic dermatitis.

 

Etiology of Allergic Rhinitis

• Allergic rhinitis is caused by things that trigger allergies, called allergens.

• These allergens can be found both outdoors and indoors.

• When allergic rhinitis is caused by common outdoor allergens such as mold or trees, grass

and weed pollens—it is often referred to as seasonal allergies, or ‘hay fever.’

• Allergic rhinitis may also be triggered by allergens that are in your house, such as animal

dander (tiny skin flakes and saliva), indoor mold, or the droppings of cockroaches or

house dust mites

 

Clinical Features of Allergic Rhinitis

Symptoms of Allergic Rhinitis

• Sneezing

• Itching (of nose, eyes, ears, and Palate)

• Rhinorrhea

• Postnasal drip

• Congestion

• Anosmia

• Headache

• Ear ache

• Tearing

• Red eyes

• Eye swelling

• Fatigue

• Drowsiness

• Malaise

 

Signs of Allergic Rhinitis

• The mucosa of the nasal turbinates may be swollen (boggy) and have a pale, bluish-gray

color.

• Some patients may have predominant erythema of the mucosa.

• Assess the character and quantity of nasal mucus.

• Thin and watery secretions are frequently associated with allergic rhinitis, while thick and

purulent secretions are usually associated with sinusitis.

• However, thicker, purulent, colored mucus can also occur with allergic rhinitis.

 

Diagnosis, Differential Diagnosis and Management of Allergic Rhinitis

Diagnosis of Allergic Rhinitis

• Normally depends on

History

• Important elements include an evaluation of the nature, duration, and time course of

symptoms, possible triggers for symptoms, response to medications, co-morbid

conditions, family history of allergic diseases, environmental exposures, occupational

exposures, and effects on quality of life.

• A thorough history may help identify specific triggers, suggesting an allergic etiology

for the rhinitis.

Trigger Factors

• Determine whether symptoms are related temporally to specific trigger factors.

• Symptoms and chronicity.

• Determine the age of onset of symptoms and whether symptoms have been present

continuously since onset.

• While the onset of allergic rhinitis can occur well into adulthood, most patients develop

symptoms by age 20 years.

Response to Treatment

• Response to treatment with antihistamines supports the diagnosis of allergic rhinitis,

although sneezing, itching, and rhinorrhea associated with non-allergic rhinitis can also

improve with antihistamines

Co-morbid Conditions

• Patients with allergic rhinitis may have other atopic conditions such as asthma or atopic

dermatitis.

• Of patients with allergic rhinitis, 20% also have symptoms of asthma.

Family History

• Because allergic rhinitis has a significant genetic component, a positive family history for

atopy makes the diagnosis more likely.

• A greater risk of allergic rhinitis exists if both parents are atopic than if one parent is

atopic.

• The cause of allergic rhinitis appears to be multifactorial, and a person with no family

history of allergic rhinitis can develop allergic rhinitis.

Environmental and Occupational Exposure

• A thorough history of environmental exposures helps to identify specific allergic triggers.

This should include an investigation of risk factors for exposure to perennial allergens (e.g.,

dust mites, mold, and pets).

• Risk factors for dust-mite exposure include carpeting, heat, humidity, and bedding that

does not have dust mite–proof covers.

• Skin tests can be done to decide for sure which allergens cause symptoms.

 

Differential Diagnosis

• Allergic rhinitis needs to be differentiated from a viral upper respiratory infection (URI)

or sinusitis.

• Symptoms of allergic rhinitis are often seasonal and may include clear watery anterior

and posterior nasal discharge, sneezing, and itchy eyes and nose.

 

Treatment

• The best treatment is to avoid what causes your allergic symptoms in the first place.

• It maybe impossible to completely avoid all your triggers, but you can often take steps to

reduce exposure.

• Treatment prescribed depends on the type and severity of symptoms, age, and whether

there are other medical conditions (such as asthma).

• For mild allergic rhinitis, a nasal wash can help remove mucus from the nose.

Antihistamines

• Antihistamines work well for treating allergy symptoms, especially when symptoms do

not happen very often or do not last very long.

• Antihistamines taken by mouth can relieve mild to moderate symptoms, but can cause

sleepiness

• Some antihistamines cause little or no sleepiness. They usually do not interfere with

learning. These medications include fexofenadine and cetirizine.

• Azelastine is an antihistamine nasal spray that is used to treat allergic rhinitis.

Corticosteroids

• Nasal corticosteroid sprays are the most effective treatment for allergic rhinitis.

• They work best when used for a long term, but they can also be helpful when used for

shorter periods of time.

• They are safe for children and adults.

Decongestants

• Decongestants may also help reduce symptoms such as nasal congestion.

• Nasal spray decongestants should not be used for more than 3 days.

Prognosis

• Most symptoms of allergic rhinitis can be treated.

• Some people (particularly children) may outgrow an allergy as the immune system

becomes less sensitive to the allergen.

• However, as a general rule, once a substance causes allergies for an individual, it can

continue to affect the person over the long term.

 

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