Introduction to TCM

Basics of TCM

  • Yin-Yang | Five Elements

Zang-Fu Theories

  • Zang Organs | Fu Organs

Classification of Antineoplastic Herbal Medicines

Characteristics of Herbal Medicines


  • By Auscultation & Olfaction
  • By Inspection


Theories of Channels (Meridians) and Collaterals

Reference: A Modern View of the Immune System

Differentiation of Syndromes

  • 8 Principles
  • 6 Channels 4 Stages
  • Syndromes of Zang-Fu Organs


  • Exogenous | Pestilential
  • Pathogenic Factors
  • Emotional

Materia Medica

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Eight Extra Channels

The eight extra channels are the following group of eight channels: Ren, Du, Chong, Dai, Yinwie, Yangwei, Yinqiao, and Yangqiao. They differ from the twelve regular channels in that they neither pertain to any zang or fu organ, nor do they share an exterior-interior relationship between each other. Their main function is to regulate the circulation of qi and blood in the twelve regular channels. When these regular channels are overfull, excess qi and blood flow into the eight extra channels to be stored for later use.

1. The Ren Channel

The Ren channel connects with all the yin channels of the body and is therefore known as the "sea of yin channels." In women, it is responsible for pregnancy and foetal nourishment.

The Ren channel commences within the lower abdomen and exits at the perineum (1). It ascends anteriorly to the public region (2). Along the internal abdomen, it flows upward to pass through Pt. Guanyuan of Ren and other points, and reaches the throat (3). Flowing further upward, it curves around the lips (4), passes through the cheek (5), and emerges in the infraorbital region (6).

Main pathological changes: hernia, leukorrhea, lumps in the lateral lower abdomen, irregular menstruation, abortion, infertility, etc.

2. The Du Channel

The Du channel governs all the yang channels of the body, so it is known as the "sea of yang channels."

The Du channel commences within the lower abdomen. Traveling downward, it appears in the perineum (1). It then flows upward inside the spinal column (2) to the nape of the neck, Fengfu (3), entering the brain and ascends to the vertex (4). Along the forehead, it descends to the nose bridge, then to the lips (5), entering the labial frenulum inside the upper lip (6).

Main pathological changes: stiffness of the spine, opisthotonos, pain of the back, mental disorders, infantile convulsion, etc.

3. The Chong Channel

The Chong channel regulates the circulation of qi and blood of the twelve regular channels, so it is known as the "sea of the twelve regular channels" and the "sea of blood."

It originates in the uterus (1) where three branches immediately arise. The first branch travels along the posterior wall of the abdominal cavity, then ascends and runs inside the spinal column (2). The second branch travels up to the umbilicus along the anterior wall of the abdominal cavity (3) and spreads in the chest, then flows upward to the throat (4) and circles around the lips (5). The third branch descends and emerges in the perineum (6), and runs downward along the medial aspect of the thigh (7), terminating at the big toe (8).

Main pathological changes: irregular menstruation, amenorrhea, uterine bleeding, deficient lactation, hematemesis, etc.

4. The Dai Channel

The Dai channel possesses the function of binding and restricting other channels. It starts below the hypochondriac region (1), runs obliquely downward, then transversely around the waist like a belt (2).

Main pathological changes: abdominal distension and coldness of the lumbar region, like "sitting in water."

5. The Yinwei Channel

The Yinwei channel binds the six yin channels together and joins with the Ren channel. Commencing from the medial aspect of the lower leg (1), it runs along the medial aspect of the thigh (2) up to the abdomen (3) to meet with the Foot-Taiyin channel. It then passes through the chest (4) and communicates with the Ren channel at the neck region (5).

Main pathological changes: heart pain, mental depression, etc.

6. The Yangwei Channel

The Yangwei channel connects with the six yang channels and communicates with the Du channel. It originates at the lateral side of the heel (1). Running upward to the external malleolus (2), it ascends along the gall bladder channel of the Foot-Shaoyang up to the hip region (3). Passing through the posterior aspect of the hypochondriac (4), axillary, shoulder and neck regions (5), it further travels upward to the cheeks (6) and forehead (7), then turns backward to the back of the neck, where it meets with the Du channel (8).

Main pathological changes: alternate chills and fever, low back pain, etc.

7. The Yinqiao Channel

The Yinqiao channel has the function of controlling the movements of the lower limbs and eyelids. It starts from the posterior aspect of the navicular bone (1), and ascends to the anterior aspect of the thigh (3), to the external genitalia (4), it ascends further along the medial aspect of the chest (5) to the supraclavicular fossa (6). It then passes through the anterior aspect of Pt. Renying (7) up to the zygoma (8), and reaches the inner canthus to communicate with the yangqiao channel (9) and Foot-Taiyang channel.

Main pathological changes: inward splay-foot, sore throat, hypersomnia, retention or urine, etc.

8. The Yangqiao Channel

The Yangqiao channel regulates the movements of the lower limbs and eyelids. It starts from the lateral side of the heel (1). Ascending along the lateral malleolus, it passes the posterior border of the fibula. Then it runs upward along the lateral aspect of the thigh to the abdomen and the lateral aspect of the hypochondriac region, where it winds over the shoulder (2), passes through the neck to the corner of the mouth (3) and enters into the inner canthus to meet with the Yinqiao channel. It runs further upward along the urinary bladder channel of the Foot-Taiyang to the forehead and communicates with the gall bladder channel of the Foot-Shaoyang at the nape of the neck (4).

Main pathological changes: outward splay-foot, insomnia, pain in the inner canthus, etc.

Traditional Chinese Medicine pages by Raymond Cheng, PhD DPA FRSA FRSPH

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With over 3000 years of experience, Traditional Chinese Medicine (TCM) has remain one of the many fascinating areas in ancient Chinese culture. First known to be documented in the Yellow Emperor's Canon of Medicine, TCM is believed to have been practised in as early as 475 to 221 B.C. The field of working knowledge of TCM stretches from anything related to general healthcare practice to the philosophy of the mind, the logic of life, religion, and even to as far as cosmology and astronumerology. This is why in order to thoroughly understand the concepts behind TCM, one must be comprehensive in learning and embracing the Chinese culture as a whole.

Just as Douglas Hoff put it when he explained about accupuncture, "The systems of TCM uses the concepts of elements and meridians and are completely immersed in the Asian cosmology which takes shape through the religions." The meridian-brain mechanism, the fundamental working concept of acupuncture, in which the pain block from the message that the needle or burning cone of herbs gives to the point of stimulus, was only found centuries later by the West through science and technology.


Raymond Cheng, PhD DPA Thank you for visiting this TCM and acupuncture information website. If you have previously been to this website, you might have noticed that some of the pages on ancient historical ideas and holistic thinkings related to Chinese metaphysics are temporarily taken offline. This is because I will be revamping the whole website and be moving those information into a new \"Ancient Chinese Culture\" section so as to reflect a more current perspective on the interpretation of some of the fundamental concepts as well as to include some of the latest information in the area. But if you have just found this website for the very first time, I welcome you again and wish you could find what you require and, hopefully, you could also be benefitted from reading the articles I published on this website.

Please be patient and do come and check out this website frequently as it's being revamped.

Raymond Cheng, PhD DPA FRSA FRSPH

March 28, 2020.


This website is published, edited and designed by Raymond Cheng, and reflects only and only his personal views and opinions in his individual capacity. The information available at this website is not intended directly or by implication to either diagnose or treat any medical, emotional, or psychological condition or disorder. It is also not intended to create a physician-patient relationship between you and I or between you and Wyith Institute™ and The Office of Dr Raymond K K Cheng. The information here is not a substitute for advice and treatment provided by your physician or by another healthcare professional. It is always recommended that consultation with local healthcare providers be obtained for any of your specific health or medical concerns. Furthermore, any products that can be purchased (yet you can see I don't have much to sell here) through advertisers' banners or through links to other websites are not either explicitly or implicitly given any warranty or endorsement by me, my colleagues, Wyith Institute™ or any of its associated businesses.