TCM knows very little about the cause of multiple sclerosis (MS). However, the typical symptoms of multiple sclerosis such as limb weakness, vertigo, incoordination and even paralysis are mainly attributed to dysfunctions in the lung, liver, spleen and kidney. It is possible that the organs are attacked by exogenous factors like heat, dryness, dampness and wind evils, which give rise to yang-qi failing to ascend upward to nourish the brain. Furthermore, TCM holds that a well organized internal environment ensures the production of marrow (which is chiefly derived from kidney essence and food nutrients). The marrow not only fills the bone, it also makes up the brain and spinal column, and thus TCM calls these structures the "sea of marrow". Long-term disharmony or emotional stimulation will affect the production of marrow particularly when the kidney is involved, leading to problems in the central nervous system.

Generally, the pathogenesis of MS can be divided into the following aspects:

Deficiencies in the spleen and stomach
In TCM, one of the major functions of the spleen and stomach are transforming food into nutrient essence that is used to manufacture qi and blood. Under-functioning will lead to malabsorption and indigestion, and dampness or phlegm will accumulate. When dampness or phlegm interferes with the ascending movement of yang-qi to the head region, vertigo occurs. On the other hand, due to the impairment in the transformation of blood and qi, head orifices and the sea of marrow will lose nourishment, leading to the development of speech difficulties or visual problems. When there are inadequate nutrients to bones, muscles and tendons, associated symptoms appear. Improper diet is an important cause of these symptoms.

Invasion of external dampness evil
This is contracted by living in damp places, sitting on damp grass, failing to dry oneself after swimming, being exposed to damp weather when wearing inadequate clothes or being exposed to foggy weather. The dampness evil tends to invade the meridians in the limbs; they cause obstruction and lead to heaviness, numbness and tingling sensations. When the damp circumstances last for a long time or are repeated, the accumulated dampness evil can turn into internal heat, which will then cause further damage to the organs, and result in various symptoms.

Flaring up in lung heat
Normally, the lung is responsible for distributing the nutrient essence throughout the body; this distribution function is carried by the lung fluid, which works to nourish the muscles, tendons, bones and vessels and also acts as the material base for normal functioning of the other organs. Acute febrile disease caused by exogenous evils invasion e.g. wind, heat, or coldness, usually damage the lung and lead to lung fluid being consumed and therefore depleted. Sometimes, a heated lung can also be induced by excessive internal heat and dryness evils. Depletion of lung fluid leads to insufficient nourishment in the above mentioned structures and result in related manifestations.

Impairment of the liver and kidney
In TCM, liver stores blood and rules tendons, and kidney stores essence and rules bones. Having a long-term chronic disease, being sexually active, overstraining oneself, suffering from an emotional disturbance or accumulation of damp-heat evils in the lower burner lead to liver and kidney damage. This leads to a depletion of kidney essence. As a result, there are inadequate supply to the bones, tendons and meridians, leading to the development of multiple sclerosis.

Click to see illustration of MS development from a TCM perspective.