Western Medicine

Contact dermatitis - allergen caused rash with well-defined border
(Guide to Medical Cures and Treatments)

Allergic contact dermatitis, also known as contact eczema, is an inflammatory skin disease caused by T-cell-mediated hypersensitivity to an environmental allergen . Both sensitization and elicitation of the reaction involve contact of the allergen with the skin. Allergens causing the disease are numerous, are common, and include both natural and synthetic chemicals.

Chinese Medicine

Contact dermatitis - caused by lacquer

Contact dermatitis describes an acute inflammatory condition of the skin or mucosa that results from contact with certain irritant substances or stimulants. The condition occurs in all ages and both sexes, but there is a higher incidence in children than the elderly and women are more commonly affected than men. A characteristic of the disease is a history of exposure to allergenic substances prior to the inflammatory episode. Such substances or stimulants can include medicated plasters, ointment, lacquer, plants, certain materials used in clothing and contact with animals. The distribution of the lesions on the skin corresponds to the points of contact with the irritant and is largely limited to those areas.

The disease has an acute onset. Typical symptoms include itchiness, a burning sensation, and swelling and tenderness of the lesions. Systemic involvement can occur in severe cases. Once irritants are removed and proper treatment given, the condition will usually resolve within one to two weeks. However, further exposure to the causative agent will cause a re-occurrence.
In traditional Chinese medicine (TCM) contact dermatitis is not recognized as a disease as such, but as a collection of symptoms. From a TCM viewpoint, diseases of the skin are included in the category of surgical trauma and they are described in many ancient surgical classics. As there is no general term in TCM for contact dermatitis, the condition is referred to by names which describe both symptoms and causative agent. Examples of these include:

"lacquer sore"

"plaster rubella" from Chinese herbal poultices

Application of Chinese herbal poultice

"commode ringworm" (inflammation of the buttocks caused by newly lacquered, old-style commode seats)

"pollen sore", and

"tar sore"(tar was formerly commonly used in China to waterproof furniture.)

Western Medicine

The disease occurs worldwide and affects both sexes and all age groups. It is common, occurring in up to four per cent of some populations. The range of potential sensitizing allergens is enormous, but a relatively small number of substances accounts for most cases. The most common examples are:

nickel (in costume jewelry and buckles)

chromate (in cement)

latex (in rubber gloves)

perfume (in cosmetics and air fresheners), and

plants (such as Primula or the Compositae).

Allergic contact dermatitis is mediated by T-cell hypersensitivity in the skin. Two phases of the disease are recognized:

Induction phase: This is the period during which a person is exposed to an initial allergen and the body's T-lymphocytes (cells of the immune system) respond and become sensitized.

Elicitation phase: When re-exposure to the same allergen occurs, the sensitized T-lymphocytes mount an increasing response and contact dermatitis results.

The induction phase can be as short as seven to 10 days after first skin contact, but it usually takes many months or years of exposure to small amounts of allergen to induce sensitization. Individual sensitivity varies according to the nature of the chemical, its concentration and the genetic susceptibility of the person exposed. Once sensitization occurs, it lasts for years, if not for life, and is generalized.
Re-exposure to the relevant allergen triggers the elicitation phase and produces dermatitis. Reactions can be elicited anywhere on the skin. In some instances systemic reactions have been provoked when the allergen enters the body by ingestion or injection.

Chinese Medicine

The lungs and spleen have a powerful influence in contact dermatitis as they are the main organs that promote and support skin function. In TCM, skin and hair are the barriers ofexogenous evils invasion, theprotective qi that enhances its integrity is regulated by the lungs. Therefore skin diseases are always viewed as indicating a lung disharmony. The spleen is responsible for extracting nutrients from food and for transporting fluids throughout the body, and impaired function can contribute to unhealthy skin and swelling. In TCM, it is considered that contact dermatitis can be caused by both endogenous (originating from inside the body) and exogenous (originating from outside the body) factors.

Inborn susceptibility (endogenous causes)
The incidence of contact dermatitis is influenced by body constitution and is more likely to occur in individuals with a congenital/inherited predisposition to the disorder. In cases of congenital deficiency, the skin and tissues beneath are loosely bonded. This means that the protective qi is weak and that the body is more prone to a flare-up of fire evil or to the development of internal wind evil . Contact with certain substances, such as lacquer, drugs, plastic, rubber products, dyes or plants, facilitates transformation of heat evil internally in the body. The conflict between blood and qi against the heat evil triggers the skin disease.

Environmental pathogen invasion (exogenous causes)
In situations where external pathogens are allowed to invade the body directly, excessive fire evil will develop and accumulate. Circulation of blood and qi in the surface areas of the body becomes disturbed and does not flow smoothly. This in turn damages the integrity and function of the skin causing dermatitis.

Click here to see the causes of contact dermatitis from a TCM perspective

 

Western Medicine

The skin eruption appears acutely with redness, swelling and clutches of small vesicles (very small blisters). In severe cases there may be extensive blistering, scaling, and weeping. In chronic milder disease, papules (raised spots) and scaling are more prominent. The lesion is itchy and may be painful if severe. The rapidity of onset after contact is directly proportionate to the degree of sensitivity and may range from six hours to several days.
The location of the eruption on the skin is helpful in diagnosing the cause. Certain areas of skin, such as the eyelids, react more easily than others, such as the palms. Metal dermatitis, usually caused by sensitivity to nickel, appears in discrete patches corresponding to the area of contact with jewelry, watches, or metal objects on clothing. A variety of allergens , such as dyes and fabric finishes, are found in clothing, causing a skin eruption on areas of skin covered by the apparel. Volatile allergens, such as perfumes and essential oils, affect exposed areas, usually the face and arms. Rhus dermatitis from poison oak or poison ivy, native to North America, produces an especially severe disease with prominent vesicles and large blisters. Characteristic streaks of vesicles arise that correspond to brushing of the skin by the plant leaves.

Chinese Medicine

The main symptoms of contact dermatitis are the appearance of a rash accompanied by an itchy, burning sensation and swelling. The rash may develop into clusters of red papules (raised spots) or, in severe cases, blisters. Scratching of the rash causes exudation (leakage) and an exacerbation of the irritation. On rare occasions, swelling and tenderness of the eyelids, lips and perineum can occur.
Contact dermatitis usually results in excessive stimulation of body functions. It is described in TCM as an asthenia syndrome and results from a relatively strong body-resistance in fighting excessive pathogens . The usual presentation in an asthenia syndrome is fever, thirst, irritability, abdominal discomfort, constipation and dark-colored urine. Severity varies with the progression of the disease.
TCM practitioners will examine the sufferer and categorize the symptoms under special syndrome groups known as "disharmony patterns." Certain disharmony patterns are present during the different stages of the disease. Contact dermatitis can be classified into the following types:
Excessive fire accumulation
This form of contact dermatitis presents with acute onset. The skin at first appears pink, or with a red rash, and there is a distinct margin and edematous accumulation of fluid in the tissues base. The rash then develops into clusters of papules (raised spots) and is accompanied by a burning sensation and itchiness. Associated systemic symptoms include mouth dryness, thirst, fever, irritability, dark urine and constipation.
Excessive fire mixed with dampness
This is a more serious form of the condition. The red papules are edematous and blisters develop which may be as large as an egg-yolk. If the rash is scratched, fluid will leak out. The rash can be extremely itchy and the lesion may become swollen and create a sensation of burning. Systemic upset includes mouth dryness and poor appetite.
Blood deficiency accompanied by wind and dryness accumulation
With repeated relapses of the disorder, the skin lesions become thickened, dry and scaly. The lesion may also develop lichen-like changes (skin develops a thickened leathery appearance). The severity of the irritation results in scars on the skin from excessive scratching.

Western Medicine

The diagnosis of contact dermatitis depends on a careful medical history, the distribution of the lesions, and patch-testing. Reactions may appear suddenly, or they may present as a chronic, low-grade, smoldering dermatitis. Possible exposures in the home, work, and recreational environment to potential allergens need to be monitored.

Skin patch-testing

The diagnosis is confirmed by patch-testing, a time-honored, well-standardized procedure that is both a test of the skin's immunity and a provocation test that reproduces the disease "in miniature". In the patch test, a suspected contact dermatitis sensitizing agent is applied to normal skin (usually on the upper back) and covered. The patches are removed after 48 hours and the underlying skin examined, with a repeat examination after a further two days. In a positive response, there is inflammation and hardening of skin at the test site. Although there are pitfalls in interpretation, patch-testing is indispensable in the investigation of allergic contact dermatitis.

Chinese Medicine

Diagnosis in TCM places importance on determining the circumstances and manifestations of a disease through inquiry and symptom observation. Diagnosis is based on the traditional four examination techniques:

Questioning The TCM practitioner will establish the medical history of both the patient and his family.

Observation Examination of the physical features of the body, such as the face, tongue, hair, nails, sputum (mucus that is coughed up), and location of pain, all offer clues to the problem. The tongue is a particularly useful indicator of the functioning of the internal organs.

Listening and smelling The smelling of sputum and breath and listening to the sounds produced by the chest offer additional clues to the patient's health.

Touching Feeling the pulse is a cornerstone of TCM diagnosis and gives the practitioner much information about any bodily imbalance.

Contact dermatitis is commonly diagnosed by the following disharmony patterns:

Excessive heat accumulation
From the TCM viewpoint, all allergenic substances are regarded as evils or pathogens . Hypersensitive reactions of the body are the result of accumulation of evils, impaired functioning of organs or disruption to the circulation of blood and qi. The pathogens induce internal changes and encourage the accumulation of excessive heat evil . This disturbs the movement of qi and blood in the skin and gives rise to a burning itchy rash. On examination the tongue is red and covered by a thin layer of yellow fur. The pulse is taut and slippery.
Excessive fire mixed with dampness
The lungs have an important role as regulator of the protective qi . The spleen provides nutrients for the skin. If the lungs and spleen are functioning poorly, external pathogens can readily invade the body and fire and dampness evils accumulate. The evils stagnate on the skin meridians causing the appearance of a bullous or blistered rash with edema and leakage of fluid. On examination, the tongue is red and covered with a yellow greasy fur. The pulse is slippery and rapid.
Blood deficiency and wind and dryness accumulation
If the spleen is not functioning properly, there is a decline in acquired jing (essence) and nutrients in the body and this affects the production of blood. This reduction in blood supply causes the skin to lose nutrients. It becomes prone to the development of wind evil and this can turn into dryness evil. The skin appears dry, scaly and thickened. On examination, the tongue is pink and covered with a thin fur. The pulse is taut, thready and rapid.
Differential diagnosis
Contact dermatitis can be differentiated from other skin disorders such as acute eczema and facial erysipelas (an acute bacterial infection of skin) by the following features:

In acute eczema, the skin lesion may appear in several forms, there is symmetrical distribution in certain locations and the margins of the rash are usually hard to identify. The condition is of longer duration and can become chronic. There is no obvious contact history with particular substance that could be responsible for the skin condition.

Facial erysipelas presents with severe systemic symptoms such as chills, high fever, headache and nausea. The rash appears as a red patch of inflamed skin with underlying swelling. The edge of the patch is palpably raised and clearly defined. There is a burning sensation in the lesion and it is tender but not itchy. There is not contact history.

Western Medicine

Several approaches can be used in treatment:

The disease responds to systemic (by injection) corticosteroids, which should be given as early as possible.

Small localized areas of involvement can be treated with a topical steroid cream.

Applications of cool, wet dressings containing Burow's solution (aluminum acetate) are helpful for treating acute lesions. The lotions are astringent and reduce swelling.

Chronic lichenified dermatitis (where skin has a thickened leathery appearance from constant scratching), which is extremely itchy, requires a potent fluorinated steroid ointment with an occlusive dressing to relieve itching and swelling.

Extensive areas of involvement or severely blistered lesions should be treated with a short but high dose of prednisone by mouth, or with intramuscular triamcinolone or methylprednisolone. .

An antibiotic may be indicated for secondary infections that result from bacterial invasion of skin that is already compromised or broken by contact dermatitis.

Antihistamines are generally not effective for controlling itching in contact dermatitis.

Chinese Medicine

Internal Therapy

Traditional Chinese medicine aims at a holistic approach. Skin diseases are associated with internal disharmony between yin and yang and are the superficial presentations of internal damage.

1.	Excessive heat accumulation

Therapeutic aim:To eliminate heat and toxic materials, cool the blood and clear the rash.

Prescription 1: Puji xiaodu dissolution drink (reduces rashes of the face and head).

ban lan gen	isatis root
lian qiao	large head atractylodes root
huang qin	baical skullcap root
huang lian	golden thread
yuan shen	figwort root
ma bo	puff-ball
niu bang zi	great burdock achene
bo he	peppermint
jiang can	stiff silkworm
chen pi	dried tangerine peel
jie geng	platycodon root
chai hu	Chinese tororwax root
sheng ma	cimicifuga rhizome
gan cao	liquorice root

Prescription 2: Liangxie jiedu decoction (for rashes on other parts of the body).

shang di	dried rehmannia root
chia hao	red peony root
jin yin hua	honeysuckle flower
lian qiao	weeping forsythia capsule
ban lan gen	isatis root
pu gong ying	dandelion
ye ju hau	wild chrysanthemum flower
dan pi	tree peony bark
zi cao	gromwell root
huang qin	baical skullcap root

 

2.	Excessive heat mixed with dampness

Therapeutic aim: To disperse heat anddampness evils and to eliminate toxins and swelling.

Prescription: Longdan xiegan decoction.

chai hu	Chinese tororwax root
huang qin	baical skullcap root
long dab cao	Chinese gentian
zhi zi	Cape jasmine fruit
che qian zi	plantain seed
shang di	dried rehmannia root
dang gui	Chinese angelica
ze xie	oriental water plantain root
gan cao	liquorice root

 

3.	Blood deficiency and wind anddryness accumulation

Therapeutic aim: To disperse heat andwind evils, nourish the blood and re-hydrate the skin.

Prescription 1: Xiaofeng powder.

dang gui	Chinese angelica
sheng di	dried rehmannia root
fang feng	divaricate saposhnikovia root
chan tui	cicada slough
zhi mu	common anemarrhena root
ku shen	light yellow sophora root
hu ma	common flax
jing jie	fine-leaf schizonepeta herb
cang zhu	atractylodes root
niu bang zi	great burdock achene
shi gao	gypsum
gan cao	liquorice root

Prescription 2: Danggui decoction

sheng di	common yam root
chuan xiong	Szechwan lovage root
jing jie	fine-leaf schizonepeta herb
fang feng	divaricate saposhnikovia root
bai ji li	puncture vine caltrop fruit
dang gui	Chinese angelica
he shou wu	fleece flower root
bai shao	white peony root
huang qi	milk vetch
gan cao	liquorice root

External therapy

Of greatest importance in the treatment of contact dermatitis is the identification of the causative agent and its subsequent avoidance. Therapeutic approaches in skin lesions are also important. In order to facilitate healing, any substance used should be mild, non-stimulating and simple to apply. The following are examples:

 

	For simple rashes: Sanhuang lotion or indigo powder lotion.
	In cases of severe exudation and erosion of skin lesions: Moist dressings should be applied soaked with the following decoction:

	lu cha	green tea
	ma chi xian	purslane herb
	huang bai	amur cork-tree
	yang di cao	emilia sonchi folia
	shi wei	pyrrosia leaf
	pu gong ying	dandelion
	sang yu	mulberry leaf

	Where erosion and scarring have occurred on the skin lesion: Indigo emulsion.
	In cases of scaling, thickening, coarse or lichen skin: Black soybean-distillate ointment.
	Examples follow of some folk prescriptions which can be applied to skin lesions: 1. Fresh ground purslane herb. 2. If vesicles appear on the rash, the following decoction can be used as a wash or soak:

huang qin baical skullcap root huang bai amur cork-tree ma chi xian purslane herb ming fan alum 3. Where the lesion has been scratched and there is exudate, washing or soaking with this decoction is useful:

shang di yu fresh garden burnet root huang bai amur cork-tree

4. Fresh ground mung beans. 5. Fresh balsam pear.

Acupuncture and moxabustion
As contact dermatitis is seen as anasthenic (excessive) syndrome, acupuncture given using reduction or purgative therapeutic methods at two to four points can be helpful. Acupuncture points: chi-ze, qu-chi, he-gu, qu-ze, zu-san-li, wei-zhong, san-yin-jiao.

Dietary therapy
A congee made from mung bean and coix (raw Job's tears) seed can also be beneficial.

Western Medicine

The only means of prevention of the dermatitis in a sensitized patient is avoidance of the offending allergen. Identification and elimination of the responsible allergen is the most important goal and the following should be noted:

Nickel sensitivity: Some patients with mild nickel sensitivity can tolerate jewelry that is treated with a protective coating.

Poison ivy: Rhus dermatitis can probably be lessened, if not prevented, if the skin is thoroughly washed with water immediately after contact. Some patients appear to lose sensitivity after repeated natural exposure, a phenomenon known as "hardening", but this remains to be documented.

Industrial prevention: Preventive measures in industrial dermatitis depend on the use of protective gloves and clothing, improved ventilation, or the substitution of non-allergenic chemicals. In extreme cases (such as with chromate sensitivity in builders), it may be necessary to change occupation or hobbies.

Protective measures

Unfortunately, many common allergens are hard to identify and allergen avoidance may be difficult to achieve.

Chinese Medicine

Prevention of contact dermatitis depends on the following:

Investigation of the medical history to identify irritants for future avoidance.

If the irritant is occupation-related, working procedures should be modified or the environment improved to avoid the irritant. Precautionary measures should be re-enforced such as the wearing of protective clothing and gloves to cover the skin if working with an irritating substance.

Hot baths should be avoided when a rash is present as this may make the condition worse. Lesions should not be scratched. If Western drugs are needed, they should be applied only under medical advice.

Hot baths worsen the condition

Dietary measures
From the TCM viewpoint, both food and drugs come from the same source and food can vary in character. This means that food can promote health or have an adverse effect on it. Seafood, spicy and hot food trigger the body to produce more wind, heat or dampness evils, which are causative factors in contact dermatitis. In TCM, dietetic restraint is urged, meaning that some foods should be avoided in certain disorders or while certain medicines are being taken. For example, intake of salty food should be limited in persons who are edematous have fluid retention and a greasy diet avoided in cases of diarrhea. For contact dermatitis, a balanced diet should be eaten. Individuals susceptible to this disorder should avoid alcohol, and eat less seafood or spicy and hot food. Drinking plenty of water is also advisable to clean the toxins from the body and prevent illness.

Food pyramid

Western Medicine

Chinese Medicine