2. Definition
Allergic rhinitis is clinically
defined as a symptomatic
disorder of the nose induced
by an IgE-mediated
inflammation after allergen
exposure of the membranes
lining the nose
3. Natural History
Onset is common in
childhood, adolescence and
early childhood .
Symptoms often wane in
older adults, but may
develop or persist at any
age
4. Natural History
No apparent gender
selectivity or predisposition
to developing AR
May contribute to a
number of other conditions
5. Allergic rhinitis
Inflammatory disorder of nasal mucosa,
characterized by pruritus, sneezing,
rhinorrhoea and nasal congestion.
Adversely affects social life, school
performance, and work productivity;
especially in patients with severe disease
Loss of productivity, missed school and
work days, and direct costs associated
with treatment create substantial costs to
society.
Lancet 2011; 378: 2112–22
33. Second Generation AH
Improve selectivity
Hepatic and Cardiovascular
side effects of terfanadine
and astemizole
Non sedating
Demonstrated efficacy for
AR symptoms
34. Wide Therapeutic Window of Second
Generation Antihistamines
The second generation H1-
antihistamines have a rapid onset of
action with persistence of clinical
effects for at least 24 hours, so these
drugs can be administered once a day.
They do not lead to the development of
tachyphylaxis and show a wide
therapeutic window (e.g. fexofenadine)
35. Significance of wide therapeutic
window (fexofenadine)
Low H1-antihistamine dose High
Ineffective Therapeutic Window
Not tested for
adverse effects
Maximum
Studied dose
(Fexo 1380 mg)
Minimally
effective dose
(Fexo 60 mg)
Howarth PH. Advanced Studies in Medicine. 2004;4(7A):S508-512
36. Third Generation AH
Minimal side effects
Increased duration of action
Positive effect on nasal
airflow
Reduction in nasal
congestion
37. Effects of leukotrienes on airways
Increased levels in nasal fluid after
allergen challenge
Contribute to both early and late phase
Nasal congestion
Sneezing, rhinorrhea
Chemoattractant for eosinophils
Promote eosinophil adhesion
Decrease eosinophil apoptosis
38. Leukotrine Inhibitors:
Competitively block binding of leukotrines to end
organs.
Montelukast is only FDA approved Leukotrine
inhibitor
Montelukast reduces exhaled Nitric oxide, a
marker for airway inflammation
Montelukast works through LC C4 and D$ which
are found in upper airway
Because Montelukast acts throughout the airway
this agent is a good choice for those with
concurrent Asthma and AR
39. Rationale for antihistamine-montelukast
combination in AR
Histamine
Responsible for rhinorrhea, nasal itching
and sneezing
Less evident effect on nasal congestion
Leukotrienes
Increase in nasal airway resistance and
vascular permeability
Blockage or inhibition of these two
mediators may provide additional benefits
compared to single mediator inhibition
40. Intra-nasal Steroids
Work mostly locally, thus avoid
unwanted side effects associated
with their oral or I/V use
• Newer formulations show even
lower systemic absorption
• Most effective against late-phase
mediators with some effect on
acute phase response.
41. Intra-nasal Steroids
Should be used in a chronic
manner
Higher dose results in greater
benefit
Judicious use in children and
pregnant women recommended
Large paed studies have not
shown significant adverse effects
42. Intra-nasal Steroids
First line drug in seasonal AR
However for perennial AR management
with I/N steroids alone has not proved to
be as beneficial
Depending upon severity of disease short
courses of oral steroids in addition to
topical symptomatic relief more
Fewer side effects (IOP)
44. Algorithm for management of AR
Allergic Rhinitis
Intermittent Symptoms Persistent Symptoms
Mild Moderate/Severe
Mild
Moderate/Severe
• Oral H1 Blocker
• Intranasal H1
Blocker
• Leukotrine
modifier
• Intranasal Steroid
• Oral H1 Blocker
• Intranasal H1 Blocker
• Nasal Cromone
• Leukotrine modifier
In PAR Pt. FU after 2-4 wks.
If failure step up, if improved continue for one month
Intranasal Steroid
Follow up after 2 wks.
Improved Failed
Step down
Review Dx
Compliance
Intranasal
Steroid
Itch/sneeze add
H1 Blocker
Rhinorrhea add
Ipratropium
Blockage: add oral
decongestant/steroid short term
45. Immunotherapy
Involves the sequential
administration of antigen to
patients with symptomatic, atopic
conditions to induce tolerance to
offending antigens
Effective in treatment of both AR &
Asthma
Generally safe and well tolerated
47. Selections of candidates for IT
Symptoms induced by allergen
exposure
Patients with rhinitis and
symptoms from lower airway
during peak allergen exposure
Insufficient control of symptoms
with AH and/or topical steroids
48. Summary…
Allergic rhinitis is associated with several co-
morbidities and affects quality of life and
productivity
Second generation antihistamines are
recommended for treatment of allergic rhinitis in
adults and children; fexofenadine has proven
efficacy, is devoid of sedation and has wide
therapeutic window
Leukotrienes play key role in allergic rhinitis;
montelukast is most throroughly tested
leukotriene antagonist
49. Summary
Antihistamine-montelukast combination
seems to be a more effective strategy than
monotherapy in the treatment of allergic
rhinitis in patients with moderate to severe
symptoms
Fexofenadine-montelukast combination
yields significant reduction in nasal
congestion and nasal resistance in allergic
rhinitis vs. fexofenadine
51. Place in therapy for antihistamine-montelukast
combination
Allergic rhinitis with nasal
congestion
Allergic rhinitis with
moderate-to-severe
symptoms