Exterior-resolving agents

Also exterior-effusing agents. Medicinals that treat exterior patterns and that are mainly used in exterior-resolving formulas.

Exterior patterns mostly arise in initial-stage externally contracted disease when external evils (usually a combination of wind with other evils) invade the body through the skin and flesh, the nose, and the mouth. External evils tend to settle first in the body’s exterior and the lung. Exterior patterns are most commonly caused by wind-cold or wind-heat. There are variations in the patterns these evils cause, and sometimes evils other than wind, cold, and heat are involved.

Exterior patterns are characterized by sudden onset, aversion to wind or cold, heat effusion (fever), sweating or absence of sweating, generalized pain, and a floating pulse. Such patterns occur in patients suffering from common cold or flu. Exterior patterns may also be seen during the initial stages of measles, sore³s, water swelling, and dysentery.

Subcategories

• Warm acrid exterior-resolving agents
• Cool acrid exterior-resolving agents

Pathomechanisms

The exterior and its protector, defense qì: The exterior is the outer surface of the body. In Chinese, it is often called the fleshy exterior (肌表 jī biǎo) because it consists of the skin and flesh (as opposed to the bones and internal organs, which constitute the body’s interior). Under normal conditions, the exterior is actively protected by defense qì. Defense qì is closely related to lung qì and diffuses with it, which means that it gently flows to the outermost parts of the body to warm the flesh and prevent external evils from invading the body.

Sweating: Defense qì regulates the opening and closing of the interstices (腠理 còu lǐ), which were traditionally understood to be spaces that run through the flesh and carry sweat out of the body. Nowadays, they tend to be equated with the sweat glands, sweat ducts, and sweat pores of biomedical anatomy. Sweating is a natural function of regulating body temperature. In Chinese medicine, it is the result of yáng qì steaming the fluids of the body.

In sickness, pronounced sweating or pronounced absence of sweating is related to disturbances of the normal sweating function. Sweating may be affected by evil qì, by the strength or weakness of right qì, by yīn-yáng disharmony, and by the looseness or tightness of the interstices.

Aversion to wind or cold: When external evils invade the exterior, they obstruct defense qì. This weakens its ability to warm the flesh, so the patient experiences aversion to wind or cold. Aversion to wind is a cold, shivery feeling experienced when the body is exposed to wind or drafts. Aversion to cold is a pronounced cold, shivery sensation that is present even when the body is well covered. Both aversion to wind and aversion to cold are quite different from fear of cold. Aversion to wind and cold are of sudden onset, are experienced even in warm environments, and are usually associated with physical discomfort (such as shivers) by which people instinctively know they have caught a cold. Fear of cold is the intolerance of cold experienced by people suffering from yáng vacuity. It is of gradual onset, abates in warm environments, and is not associated with shivering.

Heat effusion: External evils that have invaded the exterior not only obstruct defense qì but also prompt a response from the body’s general forces for maintaining and restoring health, which are called right qì. Right qì supports defense qì in its active struggle against the invaders. This fierce struggle generates the heat in the fleshy exterior that we call fever.

In Chinese medicine, where fine distinctions are made between different kinds of fever and heat sensations, not all of which are associated with an actual rise in body temperature, we prefer the term heat effusion, which reflects the Chinese conception of emitting heat (发热 fā rè). Before the modern era, there were no thermometers, so abnormal increases in body temperature could not be measured objectively. Instead, the presence of heat effusion was determined by palpation and by the patient’s subjective sensations. In the case of exterior patterns, where heat effusion is accompanied by aversion to cold, the presence or absence of heat effusion is judged solely by palpation.

Heat effusion and aversion to wind or cold are the most important signs of exterior patterns. No interior patterns are characterized by the simultaneous presence of these two signs.

Generalized pain: When external evils invade the exterior, they enter the channels and obstruct the flow of qì. In accordance with the saying, when there is stoppage, there is pain, this obstruction of qì can manifest in headache, pain and stiffness of the nape and back, and generalized pain (whole-body aches). Note that an obstruction of qì giving rise to pain is normally treated with qì-rectifying agents. However, when external evils obstruct the channels and cause headache and generalized pain, exterior-resolving medicinals are used.

Floating pulse: Exterior patterns are reflected in the state of the pulse. The struggle between right and evil on the body’s periphery manifests in a pulse that feels exuberant when applying light pressure, but that is much weaker when heavier pressure is applied.

Abnormalities of sweating: Exterior patterns are often characterized by abnormalities of sweating: either a marked presence or a marked absence of sweating. sweating or absence of sweating depends on the nature of the offending evil and the state of right qì. The significance of sweating can be explained through three different patterns:

• Wind-cold assailing the exterior, giving rise to exterior repletion;
• Wind-cold assailing the exterior, giving rise to exterior vacuity;
• Wind-heat invading the exterior.

When wind-cold assails the exterior, it can give rise to a pattern characterized by absence of sweating, together with aversion to cold, heat effusion, headache and generalized pain, a thin white tongue fur, and a pulse that is floating and tight. This is called a wind-cold exterior pattern. Because cold causes contracture and tautness, when cold evil invades the fleshy exterior, the interstices close. Hence, there is no sweating. This is called a wind-cold repletion pattern.

Alternatively, wind-cold invading the exterior can also give rise to a pattern characterized by the presence of sweating, together with aversion to wind or cold, heat effusion, headache, a white tongue fur, and a pulse that is moderate and floating or weak and floating. This pattern arises when wind evil is more pronounced than the cold evil. It is often said that wind by nature causes opening and discharge. When it penetrates the exterior, it prevents defense qì from protecting the exterior and keeping it secure, and also renders provisioning-yīn (here referring to blood and fluids, from which sweat is produced) incapable of containing itself, so that it discharges outward in the form of sweat. This type of pattern is called an exterior vacuity pattern. It is treated by effusing the exterior and harmonizing defense and provisioning. The treatment of resolving the exterior in exterior vacuity patterns is often specifically referred to as resolving the flesh (解肌 jiě jī ), flesh here referring to the fleshy exterior.

The third pattern, wind-heat invading the exterior, gives rise to sweating together with heat effusion, headache, slight aversion to cold, nasal congestion without snivel, sore throat, cough with thick yellow phlegm, thirst, a red tongue with a thin yellowish-white tongue fur, and a pulse that is floating and rapid. Here, the sweating is due to the upbearing and dispersing nature of heat, which forces sweat out of the body. This type of pattern is called wind-heat exterior pattern. It is treated by resolving the exterior with coolness and acridity and by dispersing wind-heat.

How Exterior-Resolving Medicinals Work

Exterior-resolving medicinals achieve their effect by regulating the amount of sweat the patient effuses and by dispersing evils. The importance of regulating sweat is underscored by the fact that in the traditional classification of treatment methods known as the eight methods, exterior resolution is called sweating (or diaphoresis). Exterior-resolving medicinals are acrid in flavor—a property associated with an effusing and dispersing action. They free defense qì and thereby restore normal opening and closing of the interstices, so that external evils can be released from the body.

Exterior-resolving medicinals disperse exterior evils. It is on the basis of their ability to disperse either wind-cold or wind-heat that they are subdivided into warm acrid exterior-resolving medicinals and cool acrid exterior-resolving medicinals.

Among the warm acrid exterior-resolving medicinals, the degree of sweating that is promoted varies. Medicinals that cause pronounced sweating are described as promoting sweating (lit., effusing sweat) and resolving the exterior. Agents with a mild warming and dispersing action are described dispelling wind and resolving the exterior or coursing the exterior.

Cool acrid exterior-resolving medicinals generally only have a mild diaphoretic (sweat-promoting) action, since heat evil tends to induce sweating.

Exterior-resolving medicinals are either warm or cool-cold in nature. They are nearly all acrid in flavor. Exterior-resolving medicinals mostly enter the lung and bladder channels, since these are most closely associated with the exterior. They are all upfloating in their bearing, a property associated with their effusing and dispersing action.

Properties

Nature: Medicinals that disperse wind-cold are warm-hot; those that disperse wind-heat are cool-cold.

Flavor: Exterior-resolving medicinals are mostly acrid and aromatic. They are described as light and diffusing, coursing and dispersing in action (light meaning that they are upbearing and floating). Some are also bitter; they tend to dry dampness and clear heat.

Channel entry: Most enter the lung and bladder channels. The lung is connected with the skin and body hair and opens at the nose. The foot greater yáng (tài yáng) bladder channel governs the exterior of the whole body. From the point of view of bowel and visceral pattern identification, exterior patterns are associated with the lung; however, from the point of view of six-channel pattern identification, they are associated with the bladder. In modern clinical practice, the association with the lung is considered to be the most important.

Bearing: Upfloating.

Toxicity: Nontoxic. (Xì xīn, which is sometimes classified as an exterior-resolving agent in other texts, is toxic).

Actions

Exterior-resolving medicinals are described as acrid and dispersing (or acrid-dispersing). They disperse evils that enter the body through the skin and the nose and mouth. They open the interstices and effuse sweat. These actions are related to their acrid flavor and their upfloating tendency.

Exterior-resolving medicinals are also described as effusing the exterior, coursing the exterior, or dispersing exterior evils. Those that are warming will disperse cold and treat exterior cold patterns. These are described as dispersing wind-cold, dispersing cold and resolving the exterior, or resolving the exterior with warmth and acridity. Those with a pronounced ability to promote sweating are described as effusing sweat and resolving the exterior. Those with a mild warming and dispersing effect are described as dispelling wind and resolving the exterior.

Cool or cold-natured exterior-resolving medicinals treat wind-heat exterior patterns. They are often described as dispersing wind-heat, coursing wind-heat, or resolving the exterior with coolness and acridity.

Indications

Exterior-resolving medicinals treat exterior patterns caused by external contractions. These are generally characterized by heat effusion (fever), aversion to wind or cold, headache and generalized pain, sweating or absence of sweating, and a floating pulse. In some cases, there is also nasal congestion, runny nose, itchy throat, or cough and panting.

Exterior patterns are caused by wind, usually in combination with other evils. When wind invades the upper and outer parts of the body it elicits a response from the right qì—the health-maintaining force of the body. The ensuing struggle between right and evil results in heat effusion (fever) and a floating pulse. Wind obstructs defense qì, which causes aversion to wind. Wind can also obstruct channel qì, causing headache. Patterns of this kind are called wind evil assailing the exterior. Very often, wind additionally affects the normal diffusion of lung qì, causing itchy throat, cough with expectoration of phlegm, or even rapid breathing. This is called wind evil fettering the lung. Wind generally combines with other external evils, the most frequently observed being cold and heat. Both wind-heat and wind-cold can affect not only the exterior, but also the lung. Hence, Chinese medicine speaks of wind-cold fettering the lung and wind-heat invading the lung.

Wind-cold and wind-heat exterior patterns provide a simple way to understand exterior patterns. Cold damage theory and warm disease theory provide finer distinctions. Evils include not only wind, cold, and heat, but also dampness, dryness, and summerheat. However, dampness usually occurs with either heat or cold; dryness takes the form of warm dryness and cool dryness; and warm-heat evil and summerheat are both forms of heat, and can occur with dampness. Hence, most exterior patterns can be differentiated in terms of cold and heat.

Exterior patterns are observed in common cold and flu, upper respiratory tract infections, and tonsillitis. They may also be observed during the initial stages of measles, sore³s, water swelling, and dysentery. Some medicinals that disperse wind-cold or wind-heat can also relieve pain or outthrust papules (i.e., help a rash to erupt).

Wind-Cold Exterior Pattern

Pathomechanism: Wind-cold fettering the exterior.

Signs: Pronounced headache, generalized pain, aversion to cold, possibly with signs such as absence of sweating, cough producing clear thin phlegm, nasal congestion, and absence of thirst

Treatment method: Resolve the exterior with warmth and acridity; effuse and disperse wind-cold. If the lung is affected (wind-cold fettering the lung), diffuse the lung.

Wind-Heat Exterior Pattern

Pathomechanism: Wind-heat invading the exterior.

Signs: Pronounced heat signs such as cough with sticky yellow phlegm, painful pharynx or painful red swollen tonsils (traditionally called throat nodes), thirst, a red tongue, and a pulse that is rapid and floatinge. Other signs include heat effusion, aversion to wind, headache, runny nose, and, in some cases, sweating.

Treatment method: Resolve the exterior with coolness and acridity; disperse wind-heat. If the lung is affected (wind-heat invading the lung), diffuse the lung.

Combinations

Depending on whether the patient has a cold or heat pattern, choose agents that either disperse wind-cold or disperse wind-heat. Bear in mind the seasonal frequency of external contractions. In China, wind-cold is common in the winter, wind-heat is common in the spring, summerheat and dampness are common in the summer, and dryness is common in the autumn.

• Exterior patterns with dampness: Use exterior-resolving medicinals that dispel wind and overcome dampness in combination with dampness-transforming medicinals.
• Warm-heat disease with evil in the qì aspect: Use medicinals that disperse wind-heat. Combine these with heat-clearing toxin-resolving medicinals.
• External contraction in people with constitutional vacuity: Support right and resolve the exterior by combining exterior-resolving medicinals with agents that boost qì, assist yáng, nourish the blood, or enrich yīn.
• Other signs: For cough or panting with copious phlegm, add agents that transform phlegm and calm panting. For qì stagnation with distension and oppression, add qì-moving medicinals. For vomiting, add agents that harmonize the center.

Method Of Use And Warnings

Medicinals that disperse wind-cold are usually taken as a hot decoction after eating. The patient should keep well covered to help the medicinal action.

• Avoid damage to yīn: Excessive sweating can damage yīn and even yáng. Aim to produce slight sweat sweating and then stop the treatment, so that the evil is expelled from the body without damage to right qì.
• Avoid damage to blood and liquid: Liquid and blood are of the same source. Excessive sweating can damage liquid and also the blood. Therefore use exterior-resolving medicinals with care whenever liquid and blood are depleted, as in pregnant and postpartum patients, in patients with bleeding, strangury (lín), or abnormal sweating, in patients chronic sores, and in the aged.
• Adjust according to season and location: Exterior-resolving treatment should be adjusted according to season and location. In cold weather and in cold places, agents that disperse wind-cold should be used in larger quantities. In hot weather and warm places, agents that disperse wind-cold should be used in smaller quantities.
• Do not cook overly long since active constituents may be lost. They should be brought to a boil over a martial (i.e., high) flame, then simmered over a civil (i.e., low) flame for 10–15 minutes.