The skin is considered as the largest organ of human beings, with a total area of about 20 square feet (1.86 m2). It contains two layers, each with its own important parts (Fig.1):
- Epidermis, the outermost layer of the skin, provides a waterproof barrier, prevents pathogens, regulates body temperature and creates our skin tone.
- Dermis, beneath the epidermis, contains sensory nerve endings, hair follicles, sweat glands, sebaceous glands, apocrine glands, lymphatic vessels and blood vessels. The latter provides nourishment and waste removal from its own cells as well as for the epidermis.
Beneath the dermis lies the hypodermis or subcutaneous tissue. It supports skin with nutrients, attaches skin to the underlying muscle and acts as a cushion for skin [[1],[2],[3]].
Any metabolic problems of above parts may result in a skin disease. The plenty of blood and nerve distribution causes the symptoms of redness, swollen, itching, flaking, etc.
Acne (acne vulgaris, common acne) is a disease due to blockages in the follicles and sebaceous glands of skin, sometimes with infections. The excessive formation of keratin (a structural protein of skin) and sebum (skin oil), occurred with increased androgen (a sex hormone), may block the ducts of the follicular glands. If bacteria involve under this condition, it will result in inflammatory lesions (papules, infected pustules, or nodules) in the dermis around the acne. The imbalance of sex hormones during menstrual cycles, puberty and later ages contributes an important role in acne formation [[4]]. Stress and diets also affect the sex hormone, insulin, and lipid metabolisms [[5],[6],[7]], leading to the acne worsening [[8],[9]]. The interesting thing is the teenager of a few primitive isolated tribes living in Neolithic societies have no acne [[10]]. In Traditional Chinese Medicine (TCM) believes that acne was mostly related with heat, dampness, phlegm, blood stasis and imbalance of Chong channel and Ren channel from the perspective of TCM. The accumulation of phlegm and dampness was the major syndrome type [[11]].
Rosacea is a chronic, inflammatory skin condition that produces small, red, pus-filled bumps or pustules. The exact cause of acne rosacea is unclear, a variety of factors are likely to induce or aggravate the disease, including local vasomotor disorders, hair follicle insects and local recurrent infections, the use of spicy food, alcohol, hot and cold stimulation, mental stress, emotional excitement, endocrine dysfunction. In recent years, Helicobacter pylori infection and immune factors is concerned to the causes of rosacea [[12]]. From the TCM perspective, the blood stasis develops from pre-existing accumulated heat in the lungs and stomach or the disharmony of the Chong & Ren channels. If cold or wind-cold invades the face (from exposure to cold air or cold water), the skin’s exterior defenses become blocked and the cold settles in the skin preventing the ventilation of accumulated heat on the face. This combo causes local stasis of the blood and Qi. The patient’s tongue will be dull red or purple and may even have ecchymosis (dark purple spots) with a sticky yellow coating. The pulse will likely be choppy or wiry [[13]].
Psoriasis is a non-contagious, common, chronic and incurable skin disease that occurs when faulty signals in the immune system cause skin cells (keratinocytes) to regenerate too quickly – every three to four days instead of the usual 28-30 day cycle. These extra skin cells build up on the skin’s surface, forming red, flaky, scaly and inflamed lesions that can itch, crack, bleed and be extremely painful. These lesions can be very disfiguring, causes others to stare and discriminate against people with psoriasis. The disease generally affects joints, limbs, genitalia and scalp, but it can appear anywhere and even cover the whole body [[14],[15]]. In TMC, psoriasis is considered by the invasion of pathogenic wind which incubates in the yin and blood, or accumulation and stagnation of qi and blood caused by emotional upset. They were transformed into heat, and wind and heat struggle in the skin. Psoriasis may also be caused by impairment of the Liver and Kidneys, or by disharmony between the Chong and Ren channels, between the yin and the blood or between the yin and yang in the Zangfu [[16]].
Eczema (from Greek, meaning “to boil over”; often referred to as atopic dermatitis but the latter has its own defination) is a term for many different types of skin inflammation that is characterized by one or more of these symptoms: redness, skin edema (swelling), itching and dryness, crusting, flaking, blistering, cracking, oozing, or bleeding. The cause of eczema is unknown and may be complicated, involving environmental or genetic factors or their combination (Fig.5, [[17],[18],[19],[20]]).
Causes of eczema:
1. Allergen
2. Mechanical stimulation
3. Chemical stimulation
4. Microorganism infection
5. Skin dryness
6. Functional disorders of skin barrier
7. Immune reactions
8. Neuropsychiatric factors
9. Systemic reaction abnormality
10. Circulation disorders
11. Metabolic and genetic factors
According to Chinese medicine, eczema is caused by improper diet, emotional trauma and external evil invasion [[21]]. Damp and heat appear mostly in acute eczema. Blood deficiency and wind dryness appear mostly in chronic eczema [[22]].
Treatments on skin diseases
Due to the complicated pathological mechanisms on above skin diseases, there is no cure for them in Western medicine. Managements of them are usually the treatments available. Corticosteroids, such as triamcinolone (Kenacort),methylprednisolone (Medrol), prednisolone (Prelone) and dexamethasone(Decadron), can effectively reduce inflammation, itching and pain through a wide range of physiological processes, including stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels and behavior [[23],[24]]. However, they are not curative and attempt to increase more adverse effects if with long time oral or injection use, including Cushing’s syndrome, hypertension, osteoporosis, cataract, colitis, ulcer, hypogonadism, hypothyroidism, amenorrhoea, and retinopathy [24], which can mean that the “treatment” could be worse than the “disease” itself.
Western medicine sees each organ of the human body independently for their functions, while TCM believes the body as a whole, where each organ is related to each other. For example, lung can disperse and transport the wei-qi (defensive qi) and body fluid to the skin to warm, nourish and moisten the skin so as to maintain the normal functions of the skin [[25]]. In TCM, external pathological factors such as Wind, Dampness, Dryness, or Heat can invade the body and cause skin disorders. Internal imbalances are differentiated into patterns such as Blood Stasis, Disharmony of Liver and Kidney, or Blood Deficiency, and are often reflected on the skin. When skin problems are generated by internal imbalance, in addition to the topical skin care, the individual underlying problems must be addressed, in order to clear up the surface manifestation [[26]]. Therefore, the patients with skin diseases are usually prescribed with conventional formulas, such as Long Dan Xie Gan Tang for eczema, see Table below, with some modifications by syndrome differentiation of traditional Chinese Medicine.
Treatments of skin conditions with Chinese herbal medicines
Table: Chinese herbs on skin diseases
| Skin condition | Common Clinical patterns | Composition |
| Acne |
|
|
| Eczema |
|
There are many different patterns and manifestations of eczema. It’s important to talk to your practitioner about the history and onset of eczema. |
| Psoriasis |
|
There are many different patterns and manifestations of psoriasis. It’s important to talk to your practitioner about the history and onset of psoriasis. |
| Rosacea |
|
|
References:
[1] Figure of Skin from Wikipedia: http://en.wikipedia.org/wiki/Skin [2] Structure of skin: http://www.webmd.com/skin-problems-and-treatments/picture-of-the-skin [3] Structure of skin: http://www.clinimed.co.uk/Wound-Care/Education/Wound-Essentials/Structure-and-Function-of-the-Skin.aspx [4] Acne from Wikipedia: http://en.wikipedia.org/wiki/Acne_vulgaris [5] J. P. ter Horst et al: Relevance of Stress and Female Sex Hormones for Emotion and Cognition. Cell Mol Neurobiol. 2012 July; 32(5): 725–735. [6] María del Mar Romero et al: Effect of Sex and Prior Exposure to a Cafeteria Diet on the Distribution of Sex Hormones between Plasma and Blood Cells. PLoS One. 2012; 7(3): e34381. [7] Lin Manting et al: The model of rat lipid metabolism disorder induced by chronic stress accompanying high-fat-diet. Lipids Health Dis. 2011; 10: 153. [8] Noor Hasnani Ismail et al: High glycemic load diet, milk and ice cream consumption are related to acne vulgaris in Malaysian young adults: a case control study. BMC Dermatol. 2012; 12: 13. [9] Behnaz Behnam et al: Psychological Impairments in the Patients with Acne. Indian J Dermatol. 2013 Jan-Feb; 58(1): 26–29. [10] Neolithic societies: http://www.medicinenet.com/acne/article.htm [11] Guo Lian et al: earch Comment on the Treatment of Acne by Traditional Chinese Medicine. rnal of Henan University of Chinese Medicine. http://lib.cqvip.com/qk/97416B/201206/42172821.html [12] Rosacea from Baidu: http://baike.baidu.com/view/2859369.htm?fromId=64260 [13] Rosacea: http://zizaidermatology.wordpress.com/2011/05/25/rosacea-according-to-chinese-medicine/ [14] Psoriasis: http://www.medicalnewstoday.com/releases/15573.php [15] Psoriasis from Wikipedia: http://en.wikipedia.org/wiki/Psoriasis [16] Zhu Zhi Qiang: Psoriasis treatment by traditional chinese medicine. JOURNAL OF CHINESE MEDICINE NUMBER 55 SEPTEMBER 1997. http://www.jcm.co.uk/media/sample_articles/55-10.pdf [17] Eczema from Wikipedia: http://en.wikipedia.org/wiki/Eczema [18] Dyshidrotic eczema from Wikipidia: http://en.wikipedia.org/wiki/Dyshidrosis [19] Ruiyao Yu and Lingzhan Kong: Diagnosis and treatment of dermatitis and eczema. Color atlas. People’s Militery Medical Press, 2006.7. ISBN 7-5091-0328-2 [20] Jingwen Xue, Qian Xue and Pei Xue: Guide to Dermatology Diagnosis and Therapeutics. Tianjin Science & Technology Translation & Publishing Corp. 2005.5, ISBN 7-5433-1868-7 [21] Eczema by TCM: http://www.med66.com/html/2005/1/he112675640171150025928.html [22] Eczema by TCM from Baidu: http://baike.baidu.com/view/1001.htm [23] http://www.behcets.com/site/pp.asp?c=bhJIJSOCJrH&b=260550 [24] Corticosteroids from Wikipedia: http://en.wikipedia.org/wiki/Corticosteroid [25] Skin and lung: http://tcmdiscovery.com/BasicTheoryofTCM/info/20080923_361_2.html [26] TCM on skin problems: http://www.tcmpage.com/hpdermatosis.html