The immune system is generally regarded as beneficial. However, in some
cases, the immune system responds inappropriately, and all of a sudden we have
too much of a good thing. Allergy is sometimes referred to as hypersensitivity
and involves an exaggerated response to an antigen which, in this case, is
called an allergen. There are four distinct types of hypersensitivity and these
include: immediate (seasonal or respiratory allergies), cytotoxic (transfusion
reactions), immune complex (vaccine reactions), and cell mediated or delayed
hypersensitivity (poison ivy). By far the most common are the immediate
hypersensitivity reactions.
Seasonal or respiratory allergies are usually associated with plant
pollen (hay fever), but foods and insect stings may also elicit an
immediate hypersensitive reaction. It’s called immediate hypersensitivity
because inhalation of offending plant pollen, for example, causes respiratory
distress in a very short period of time. Not everyone is affected by respiratory
allergies, and even the sensitive individual suffers from allergic symptoms only
during certain times of the year. Hence we get the name seasonal allergy.
However, certain types of immediate hypersensitivity occur where the sensitive
person suffers throughout the year. To give an idea as to how widespread
respiratory allergy is, a condition known as allergic rhinitis (runny nose due
to allergy) affects 20% of all adults and 40% of the children in the U.S. (1).jc
Respiratory allergies can be caused by almost any airborne particle.
The most common triggers are animal danders, feathers, fabrics, dust, molds and
plant pollens. Allergic rhinitis caused by plant pollens is sometimes called
pollinosis or hay fever and usually occurs during certain seasons (most people
are affected during the spring or early summer). Springtime is when the most
notorious allergenic plants produce pollen that causes immediate
hypersensitivity.
When pollen (allergen) enters the respiratory system by inhalation, an
allergic reaction is triggered. This reaction begins with the allergen being
phagocytized by respiratory macrophages followed by a complex series of immune
processes that ultimately leads to the release of allergy mediators such as
histamine. These mediators are released from storage granules found in certain
white blood cells such as basophils and mast cells. These mediators,
particularly histamine, are responsible for the symptoms of respiratory
allergies. Histamine causes blood vessel dilation (inflammation), increased
capillary permeability (localized edema), brochial constriction (difficulty in
breathing), mucus secretion (runny nose), pain and itching. Anyone suffering
from seasonal allergies can identify with these symptoms. Of course, the most
logical approach to combating this unpleasant situation is to avoid the
allergen. Physicians can offer several therapies, including prescription drugs
and OTC medications. However, a variety of dietary ingredients offer immediate
symptomatic relief. A few examples of nutrients that produce relief of allergy
symptoms include:
Bitter orange fruit (Citrus aurantium) contains synephrine,
which constricts respiratory tract blood vessels and reverses histamine-induced
vasodilation. This action reduces localized inflammation and stops the runny
nose (this is sometimes called a decongestant effect) (2).
Andrographis (Andrographis paniculata) has been shown to
minimize allergic reactions by stabilizing mast cell membranes. In other words,
andrographis combats the release of allergic mediators from the mast cell
granules (2).
The flavonoid quercetin has been shown to have anti-inflammatory and
mast-cell-stabilizing effects. Quercetin will reduce many of the unpleasant
symptoms of an allergic reaction (2).
Quercetin and other flavonoids will minimize localized edema
(fluid build-up) by reducing capillary permeability and the leakage of capillary
fluid (2).
These ingredients can offer symptomatic relief of respiratory allergies and
have a long history of traditional use in soothing and cleansing of the
respiratory tract membranes. These actions promote respiratory tissue health and
support the respiratory system during seasonal changes.
Created by Dr. William J. Keller
References:
1. American Academy of Allergy Asthma & Immunology. Allergy Statistics.
1996-2009. Available at:
http://www.aaaai.org/media/resources/media_kit/allergy_statistics.stm
Accessed March 12, 2009.
2. Jellin JM, Gregory PJ, Batz F, Hitchens K,
et al. Pharmacist’s Letter/Prescriber’s Letter Natural Medicines Comprehensive
Database. 9th ed. Stockton, CA: Therapeutic Research Faculty; 2007.