FEATURE
IT’S JUST MY ALLERGIES…OH REALLY?! PART 2
History and Pathophysiology of Allergic Diseases
Editor’s Note: This is part two of a two-part
series on allergic rhinitis. Part one was fea-
tured in the July 2018 edition of Louisville
Medicine.
P
harmacologic Treatment and Symp-
tom Relief.
As it relates to treatment of aller-
gic rhinitis, practice parameters in
great detail have been published. (3, 21, 22) As noted previously,
identification of allergen and subsequent avoidance is helpful to
lower allergen burden especially as it relates to indoor allergen
reactivity (cats, dogs, mites, molds, etc.). Following avoidance
measures, pharmacotherapy is the mainstay of treatment for many
patients. However, modulation of the immune system through
immunotherapy is a disease modifying treatment and will be of
great benefit for those patients who fail medical treatment and
wish to avoid medications and pursue a better long-term solution.
limit their usefulness. A landmark study published in 2000 in the
Annals of Internal Medicine showed that taking Benadryl 50 mg
caused more impairment on a driving course than a blood alco-
hol level of 0.10% (which exceeds the legal limit in many states).
(19) The study also found that the driving impairment was not
predicted by self–reported drowsiness scores. Fexofenadine 60
mg did not result in impairment.(19) As a result of this study and
others relating to impairment, second generation antihistamines
(loratadine, desloratadine, fexofenadine, cetirizine, and levocet-
irizine) have much less impairment and sedation and should be
utilized over the first generation antihistamines.(3) Among the
second generation antihistamines, levocetirizine and cetirizine
have slightly more side effects of sedation compared to the other
second generation antihistamines.
The cornerstone of pharmacotherapy remains the use of in-
tranasal steroids with this class being the most effective at con-
trolling symptoms. Certain caveats bear mentioning. Fluticasone
propionate is indicated in non-allergic rhinitis. Budesonide nasal
In terms of pharmacotherapy, certain classes of medications
spray is pregnancy category B. Mometasone has been indicated at
address symptoms more effectively than others. Table IV provides
higher dosages to treat nasal polyps. The package inserts should be
a summary of medications and their effectiveness at relieving
consulted for approved indications, dosing, adverse reactions and
certain symptoms. (16, 17, 18)
other information, but in general, these medications are regarded
as safe and have been given OTC designation
TABLE IV. MEDICATIONS USED TO TREAT ALLERGIC SYMPTOMS
by the FDA. Local side effects can be common
Congestion Rhinitis Sneezing Itchy
Ocular Symptoms and limit their usage, including nasal irritation,
Nasal Steroid
+++
+++
+++
++
++
epistaxis, dryness and septal perforation in rare
Antihistamine Oral
+
++
++
+++
++
instances. Unlike nasal topical decongestants
Antihistamine Nasal
+
++
++
++
-
associated with rhinitis medicamentosa, nasal
Anticholinergic Nasal -
++
-
-
-
steroids may be utilized long term. (3, 21, 22)
Leukotriene Modifier ++
+
-
-
++
Nasal antihistamine sprays are also very
Cromolyn Nasal
+
+
+
+
-
effective and unlike oral antihistamines have
Decongestant
+
-
-
-
-
Ocular Antihistamine -
-
-
-
++
the unique property of improving congestion
Mast Cell stabilizer
similar to a nasal steroid. Two medications
are approved in the US, azelastine (Astelin)
As it relates to antihistamines, the use of first generation anti-
and olopatadine (Patanase). These medications are considered
histamines (diphenhydramine, chlorpheniramine, hydroxyzine,
to be second line treatment after the use of intranasal steroids.
etc.) should be avoided as somnolence, impairment, drug inter-
They have been shown to be synergistic when combined with
actions, and even cardiac side effects have been reported and
(continued on page 34)
AUGUST 2018
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