1.
Allergic Rhinitis
By
Koushik Darivemula
M. Sc Biotechnology
Kowshikrishna123@gmail.com

2.
What is Allergic Rhinitis ??
 Allergic rhinitis (AR) is an atopic disease presenting with symptoms of sneezing,
nasal congestion, clear rhinorrhea, and nasal pruritis. It is an IgE-mediated
immune response that is against inhaled antigens in the immediate phase, with
a subsequent leukotriene-mediated late phase.1
 In the past, allergic rhinitis was considered to be a disorder localized to the nose
and nasal passages, but current evidence indicates that it may represent a
component of a systemic airway disease involving the entire respiratory tract.2
 Co-morbid conditions includes Asthma, Atopic Dermatitis & Nasal polyps.3
 Allergic Rhinitis symptoms result in sleep disturbance, fatigue, depressed mood
and cognitive function compromise that impairs quality of life and productivity.3
 Around 20–30 % of the Indian population suffers from allergic rhinitis and that
15 % develop asthma.3

3.
Etiology
 Early phase: Allergic rhinitis is an
immunoglobulin (Ig)E-mediated response against
inhaled allergens that cause inflammation driven
by type 2 helper (Th2) cells, occurs within five to
15 minutes of exposure to an antigen, resulting in
degranulation of host mast cells. This releases
histamine, which is one of the primary mediators
of allergic rhinitis, induces sneezing via the
trigeminal nerve and also plays a role in
rhinorrhea by stimulating mucous glands.1
 Late phase: Immune mediators such as
leukotrienes and prostaglandins are also
implicated as they act on blood vessels to cause
nasal congestion. Four to six hours after the initial
response, an influx of cytokines, such as
interleukins (IL)-4 and IL-13 from mast cells
occurs, signifying the development of the late
phase response. These cytokines, in turn, facilitate
the infiltration of eosinophils, T lymphocytes, and
basophils into the nasal mucosa and produce
nasal edema with resultant congestion.

4.
Classification of AR based on
symptoms and severity3
Based on Symptoms
1. Intermittent - <6 weeks
2. Persistent – symptoms lasts
throughout the year
Based on Severity
1. Mild
2. Moderate- severe
Note:
• Mild symptoms includes Normal sleep, no impairment of daily
activities.
• Moderate- severe symptoms includes abnormal sleep, impairment
of daily activity.

5.
Diagnosis
 Allergic rhinitis is largely a clinical diagnosis
made based on a thorough history and
physical.1
Diagnosis tests:
1. Skin pricking test2
2. Allergen-specific IgE test2
3. Radiographic imaging, Computerized
tomography is used to exclude chronic
rhinosinusitis, tumors.3
4. The diagnosis of asthma- Asthma and
rhinitis are common co-morbidities,
suggest ing the concept of ‘‘one airway,
one disease.

6.
Treatment
 The main aim of treating Allergic Rhinitis is relief from symptoms.2
 therapeutic options include avoidance measure, antihistamines, intranasal steroids, Intranasal
corticosteroid therapy, leukotriene receptor antagonists (LTRAs), combination intranasal
corticosteroid/antihistamine sprays and allergen immunotherapy. 2
 Avoidance measure: Precautions can be taken to avoid dust mites, animal dander.1
 Antihistamines: First-generation antihistamines include diphenhydramine, chlorpheniramine, and
hydroxyzine, whereas fexofenadine, loratadine, desloratadine, cetirizine and Azelastine. 1
 Intranasal corticosteroid therapy: Beclomethasone, budesonide, fluticasone propionate, mometasone
furoate, ciclesonide, fluticasone furoate and triamcinolone acetonide are few nasal sprays used.1
 Leukotriene receptor antagonists (LTRAs): Montelukast and zafirlukast are most effective.
 Allergen immunotherapy: Allergen immunotherapy involves the subcutaneous administration of
gradually increasing quantities of the patient’s relevant allergens until a dose is reached that is efective in
inducing immunologic tolerance to the allergen. Allergen immunotherapy is given on a perennial basis
with weekly incremental increases in dose over the course of 6–8 months, followed by maintenance
injections of the maximum tolerated dose every 3–4 weeks for 3–5 years.2
 Types of immunotherapy includes Subcutaneous immunotherapy (SIT), Local nasal immunotherapy (LNIT) and
sublingual immunotherapy (SLIT).3

7.
Role of antihistamines in treating AR
 Antihistamines bind to histamine receptors on the surface of cells. There are four types of histamine
receptors in the body (H1 -H4 ), with H1 and H2 being most widely expressed.4
 H1 histamine receptors are found on a variety of cells including airway and vascular smooth muscle
cells, endothelial cells, epithelial cells, eosinophils and neutrophils.4
 H1 antihistamines (H1 receptor antagonists or H1 receptor blockers)commonly used medications in
the world not only for prevention and treatment of symptoms in allergic rhinitis.7

8.
Azelastine role in Allergic Rhinitis
 Azelastine nasal spray (Astelin® Nasal Spray) is an effective topical
management for the symptoms of seasonal allergic rhinitis. The active
ingredient, azelastine hydrochloride, is a selective, high-affinity,
histamine H1- receptor antagonist with structural and chemical
differences (it is a phthalazinone derivative) that distinguish it from
currently available antihistamines. 6
 On a milligramper-milligram basis, azelastine is approximately 10 times
more potent than chlorpheniramine at the H1-receptor site.6
 azelastine is more than just an anti-histamine. It exhibits a very fast and
long-acting effect based on a triple mode of action, with anti-
inflammatory and mast cell stabilizing properties in addition to its anti-
allergic effects.5
 Azelastine inhibits the activation of cultured mast cells and release of
interleukin (IL)-6, tryptase, and. It also reduces mediators of mast cell
degranulation such as leukotrienes which are involved in the late phase
allergic response, in the nasal lavage fluid of patients with rhinitis. 5

9.
 Other anti-inflammatory properties of
azelastine include inhibition of tumor necrosis
factor alpha (TNFα) release reduction of
granulocyte macrophage colony-stimulating
factor (GM-CSF) generation, as well as a
reduction in the number of a range of
inflammatory cytokines including interleukin
(IL)-1β, IL-6, IL-4 and IL-8.5
 Recent results from 2 studies have shown that
azelastine nasal spray at a dosage of 1 spray
per nostril twice daily is effective and has a
better tolerability profile compared to 2 sprays
per nostril twice daily in patients (12 years; n =
554) with moderate to severe SAR.5
 The 1-spray dose could be used as a starting
dose in patients with mild-to-moderate
symptoms, and if necessary the dose increased
to 2 sprays per nostril twice daily if symptom
control proved to be inadequate.5
Comparisons with intranasal
corticosteroids

10.
Comparisons with oral antihistamines
Azelastine nasal spray and cetirizine 10 mg/d were compared in a randomized, double-blind,
multicenter study in 136 patients during a 2-week study period. The total symptom scores improved
47% and 61% for azelastine and 55% and 67% for cetirizine on days 7 and 14, respectively.6

11.
Conclusion
 Azelastine nasal spray is an effective topical treatment for the symptoms of seasonal
allergic rhinitis including nasal congestion and ocular symptoms. Azelastine affects early-
and late-phase allergic reactions through interrelated effects on histamine and other
mediators of the inflammatory response.6
 Azelastine nasal spray had a relatively low incidence of somnolence (7.7%) associated with
its use in long-term studies and did not demonstrate psychomotor impairment even at oral
dosages 4 to 8 times the recommended daily dosage of azelastine nasal spray.6
 Azelastine is not associated with drug interactions and the types of adverse cardiac effects
that have been reported with terfenadine and astemizole.
 The advantages of intranasal delivery include lower risk of systemic side effects and drug
interactions, azelastine nasal spray was well-tolerated for treatment durations up to 4
weeks in both adults and children (12 years).5

12.
References:
1. Allergic Rhinitis Shweta Akhouri; Steven A. House
2. Allergic rhinitis Peter Small1 , Paul K. Keith2 and Harold Kim2,3*
3. Allergic Rhinitis: an Overview Jitendra Varshney • Himanshu Varshney
4. Antihistamines and allergy Katrina L Randall Staff specialist1 Senior lecturer2 Carolyn A
Hawkins Staff specialist1 Lecturer2 1 Department of Immunology Canberra Hospital 2
Australian National University Medical School Canberra
5. Effectiveness of twice daily azelastine nasal spray in patients with seasonal allergic rhinitis
Friedrich Horak Medical University Vienna, ENT – Univ. Clinic, Vienna, Austria
6. Management of allergic rhinitis with a combination antihistamine/antiinflammatory agent Phil
Lieberman, MD Knoxville, Tenn
7. H1 Antihistamines Current Status and Future Directions F. Estelle R. Simons* **þ§ and Keith J.
Simons