What is allergy ?
Allergy is a term used in western medicine, referring to an abnormal immune reaction to a foreign substance that is not typically harmful to the body. Allergic conditions can occur as allergic rhinitis, food allergy, hives, eczema, contact dermatitis, asthma and even a severe life-threatening situation known as anaphylaxis. Common symptoms associated with allergic reactions include running nose, sneezing, breathing difficulty, red eyes, itchiness, swelling, rashes, blisters, vomiting and diarrhea.
There is no similar term like “allergy” in Traditional Chinese Medicine (TCM); however based on the manifestations of allergy, TCM claims that allergic development is due to inherent defect of the body, meaning a special constitutional factor that make individuals susceptible to allergies.
The constitution factor for allergy is closely related to heredity. It is generally interpreted as individuals inherited inadequate congenital essence from their parents. The depleted state leads to under-nourishment of internal organs and functional weakness, in particular the lung, spleen and kidney organs; meanwhile the productions of blood and qi (vital energy), and body fluid metabolism also affected. When there are external pathogens irritating the weakened body at the same time, allergic symptoms will occur.
Where are allergens come from?
An allergen is a substance that causes an allergic reaction. Allergens are commonly found in environment, such as pollen, dust, mold, animal hair and smoke. They can be from foods too, such as additives, seasonings, peanut, nuts, egg, milk, wheat, soybean and sea products; certain drugs or insect bites can even lead to anaphylaxis. Basically, it is possible to be allergic to anything.
According to TCM theory, the external allergens such as pollen, seafood and environmental dust are exogenous disease causative factors, therefore allergic conditions are categorized as exogenous diseases. TCM also claims that there are six kinds of pathogens from the environment, allergic conditions are further differentiated from their disease natures, such as wind, heat, cold, dryness, dampness and even a mixed disease nature.
Allergy in respiratory system
The common allergies occurred in the respiratory system are rhinitis and asthma.
Allergic rhinitis is divided into seasonal and perennial types based on its occurrence. Typical features include nasal congestion, running nose, itchy nose, sneezing, itchy and watery eyes.
Seasonal allergic rhinitis usually happens in spring and summer that are relatively warm and humid weather, the allergens are mostly pollen and mold, and thus also known as hay fever. Perennial allergic rhinitis can happen any time during the year in response to indoor substances, such mites, pet dander, dust and hair.
From a TCM viewpoint, the lungs locate in the chest and open into the noses. Since the lungs in the highest position among other organs, the lungs provide protection for other organs like an umbrella.
The lungs rule qi (vital energy) and respiration, regulate water passages according to TCM theory. The lungs breathe in and out to exchange qi and regulate respiratory movements; they also smooth the water passages to regulate fluid distribution throughout the body.
When allergens are inhaled in through the respiratory track, the lungs are attacked in the first place. Coughing, shortness of breath or breathing difficulty indicate that the lungs’ dissemination, descending and purification actions are interrupted; nasal congestion, running nose and sneezing indicate that the lungs fail to regulate the water passages and fluid distribution is disturbed, which in turn formed phlegm and static fluid to block the nasal orifices.
Allergy in skin
This involves skin reactions resulted from contacts, insect bites, inhaling or ingesting allergens; typical conditions are dermatitis, eczema and hives.
Hives (medically known as urticaria) is divided into acute and chronic types, the acute cases are in majority.
Acute hives usually has a sudden onset, and present with general or localized red, itchy, raised welts on the skin in varying shapes and sizes. Occasionally, individuals may accompany abdominal pain, nausea, vomiting, and even asthma or breathing difficulty. The hives change size rapidly and move around, disappearing in one place and reappearing in other places. The skin reactions last from several minutes to ten more hours, when irritated by the same allergen, it will occur or aggravate again.
The course of chronic hives can last from months to years, some patients may experience alternative occurrences and remissions. The skin usually has welts and itching only.
Discussions about hives are widespread in many TCM classics. It is claimed that development of hives is associated with special constitution, weakened blood and qi activities, and vulnerability to external pathogens attacking in particular the wind; improper diet or emotional distress also play an influential role. The common disharmony patterns involve wind accumulating in skin, wind and coldness constraining in superficial body, damp-heat in skin, wind and dryness due to blood deficiency, flaring up of qi and nutrient phases.
Eczema is a skin inflammation that typical causes skin patches with redness, itchiness, cracks, and roughness. It is non-infectious and cannot be passed on through close contact. Eczema is divided into acute and chronic types; acute eczema only last from several hours to 1~2 days, chronic eczema occurs repeatedly that can last for months to years.
The triggering factors for eczema may be determined by heredity, which are vary from person to person, including contact substances like house dust mites, pollen, wool, molds and pet dander; foods like egg, beef, sea and daily products; even mental and autoimmune conditions play influential roles.
Eczema can occur in any region on body surface, it is more common in regions like head and face, around ears, wrists, insides of the elbows, armpits, and back of the knees. The affected skin areas become dry, itchy, red and appear blisters; overtime the skin areas turn thick, rough, cracked and pigmented; scab, peeling and weeping also appear in severe cases.
There is no disease term like “eczema” in TCM, however, it was not uncommon to be mentioned in the ancient TCM classics. This kind of skin rashes are named according to the specific affected regions, for example, “around-ear rashes,” “hand or foot rashes,” “four-curve rashes (inner elbows or back of knees),” “wet tibia rashes (lower legs),” “groin rashes,” and “oily facial rashes (head and facial regions).”
Eczema is common in babies. TCM claims that it is a kind of inherit problem, that the fetus received toxic heat from the parents during pregnancy, making the baby vulnerable to wind irritation. Wind is a leading pathogenic factor in eczema.
According to TCM theory, eczema development is due to a combination of internal and external factors. Individuals may have lung deficiency that fails to disseminate protective qi over the body’s surface; improper diet leads to spleen deficiency and damp-heat accumulated in the skin; or emotional distress leads to heart fire and over-heated blood; these internal disharmonies weaken the skin’s ability to resist external pathogens. When external pathogens such as wind, dampness, heat and coldness take advantage to irritate the skin, eczema is likely triggered.
The incidence of allergies is climbing along with the improvement of living standards. A faster pace of life, sanitized lifestyles, changed diet, increased exposure to chemicals and pollutants have all combined to make us susceptible to allergy.
Even though allergic incidences are varied in type and seriousness, they all reflect overactive responses of the immune system. Abnormal immune recognition that causes a serious of aggressive bodily attacks against something usually harmless, and finally the body itself is damaged.
Unlike Western medicine treatments that focus on exogenous factors, such as avoiding allergens, anti-allergy or desensitization therapies, conventional methods for allergies have better short-term effects, but can’t sure about the long-term relief. TCM treatments on allergic reactions focus more on the overall organ functioning and the balance state of the body. In TCM viewpoints, exogenous influential factors are somehow constant and unavoidable, allergens are a kind of “external pathogens” that can only attack the body when the body is weakened and unbalanced. Therefore, TCM treatments for allergies aim to shift the internal environment to a new balance, restore organ functioning, eliminate and cleanse the accumulated pathogenic factors, which can be more beneficial for long-term relief and less likely to relapse.