Exterior and Interior

The categories of exterior and interior form two principles, which are used to determine the depth of the diseased area and to generalize the direction of the development of a disease. The skin, hair, muscles and their interspaces, and the superficial portion of meridians and collaterals of the human body belong to the exterior, while the five zang and six fu organs pertain to the interior.

Exterior cold - Severe chills, mild fever, no sweating, absence of thirst, thin, white and moist tongue coating, superficial and tense pulse.

Exterior heat - Chills, fever, headache, general aching, thin tongue coating, superficial pulse. Mild chills, severe fever, no sweating or sweating, thirst, thin and yellow tongue coating, superficial and rapid pulse.

Exterior deficiency - Sweating.

Exterior excess - No sweating.

Exterior syndromes. Exterior syndromes refer to pathological conditions resulted from the invasion of the superficial portion of the body by exogenous pathogenic factors. They are marked by sudden onset of symptoms with short duration, and are often seen at the early stage of exogenous diseases. The chief manifestations are an intolerance to cold ( or wind ) , fever, a thin tongue coating and a superficial pulse. The accompanying symptoms and signs are headache, general aching, nasal obstruction and cough. Clinical manifestations may vary according to the invading pathogenic factors and the body constitution of the patient. They are manifested as cold, heat, deficiency and excess.

Interior syndromes. Interior syndromes refer to pathological conditions resulted from the transmission of exogenous pathogenic factors to the interior of the body to affect zang - fu organs, or from the functional disturbances of zang - fu organs. Interior syndromes cover a wide range of pathological conditions and may occur in the following three conditions : transmission of persistent pathogenic factors from the exterior to the interior of the body to invade zang - fu organs ; direct attack on zang - fu organs by exogenous pathogenic factors ; drastic emotional changes, improper diet and overstrain and stress, all of which affect zang - fu organs directly, leading to functional disturbances. For details of interior syndromes, refer to the differentiation of deficiency and excess, and to the differentiation of syndromes according to the theory of zang - fu organs.

Differentiation of exterior and interior syndromes. The accompaniment of aversion to cold with fever, and changes in tongue coating and pulse are highly significant for differentiating exterior and interior syndromes in exogenous febrile diseases. Generally, fever accompanied by aversion to cold suggests exterior syndromes ; fever with no aversion to cold, or aversion to cold with no fever indicates interior syndromes. A thin and white tongue coating, possible with red tongue borders, is often seen in exterior syndromes. The appearance of other abnormal qualities of tongue coating often indicates interior syndromes. A superficial pulse suggests exterior syndromes ; a deep pulse suggests interior syndromes.

The relationship between exterior and interior syndromes. In given conditions, exogenous pathogenic factors, if they are not expelled from the exterior of the body, may be transmitted to the interior, giving rise to interior syndromes. This is known as " transmission from the exterior to the interior. " Pathogenic factors in some interior syndromes may be transmitted from the interior to the superficial portion of the body. This is known as " transmission from the interior to the exterior. " The occurrence of the transmission mainly depends upon the relative strength of the pathogenic factor and antipathogenic qi. The transmission of pathogenic factors from the exterior to the interior is often due to weakened body resistance to disease, or to hyperactivity of the pathogenic factors, improper care, or incorrect or delayed treatment. The transmission of interior pathogenic factors to the interior is often the result of correct treatment and care, and strengthened body resistance to disease. Generally speaking, the inward transmission of pathogenic factors indicates an aggravation of the disease, while the outward transmission represents a tendency of pathogenic factors in the interior being expelled, thus indicating an alleviation of the disease.

In the process of the development of disease, there is a condition known as " the exterior and interior being diseased simultaneously. " This may appear at the early stage of a disease, when both exterior and interior syndromes are seen at the same time. This also occurs when exogenous pathogenic factors are transmitted to the interior, while the exterior syndromes are still present. Prolonged endogenous diseases complicated with recent exogenous diseases, or exogenous diseases inducing acute attacks of chronic endogenous diseases may also be the causes. As exterior and interior syndromes are usually complicated with cold, heat, deficiency and excess, many different syndromes are exhibited in " the exterior and interior being diseased simultaneously, " for example, exterior cold complicated with interior heat, exterior deficiency with interior excess, and exterior excess with interior deficiency.

Intermediate syndromes. Intermediate syndromes refer to pathological conditions in which exogenous pathogenic factors fail to be transmitted completely to the interior, while the antipathogenic qi is not strong enough to expel the pathogenic factors to the body surface. The pathogenic factors thus remain between the exterior and interior. The chief clinical manifestations are alternate chills and fever, discomfort and fullness in the chest and hypochondria, vomiting, anorexia, bitter taste in the mouth, dry throat, blurred vision and string - taut pulse. For details, refer to the Shaoyang Syndrome in the chapter " Differentiation of Syndromes According to the Theory of the Six Meridians. "