Postnasal Drip: What Does Traditional Chinese Medicine Say?

I. Starting from "The Lung Opens into the Nose": Why Does Nasal Mucus Deviate from Its Normal Path

In the Yellow Emperor's Classic of Internal Medicine·Plain Questions·Chapter on Manifestation of the Five Qi, it is recorded: "The five viscera transform into five fluids: the heart produces sweat, the lung produces nasal mucus, the liver produces tears, the spleen produces saliva, and the kidney produces spittle." This passage correlates the five secretory fluids of the human body with the five viscera, pointing out that nasal mucus is governed by the lung. The lung not only governs respiration but is also responsible for disseminating defensive qi and distributing body fluids to the body surface and the nasal orifices. When the nasal passages are unobstructed and the fluids are moistened, nasal mucus flows slowly out through the nostrils, fulfilling its physiological mission.

If nasal mucus does not flow out through the nostrils but instead flows backward into the throat, traditional Chinese medicine refers to this as "unfavorable nasal orifices with mucus spilling into the pharynx," essentially indicating an imbalance between the lung's dispersing and descending functions. What is dispersing? It is the ability to distribute fluids upward and outward. What is descending? It is the channel for clearing turbid qi downward and inward. When the two work in harmony, the nasal passages remain open and the throat stays clear. Once this balance is broken, nasal mucus seeks another route and becomes a nuisance by flowing backward.

This backflow is not simply "nasal mucus taking the wrong path"; it often signals a noteworthy deviation in the movement of qi within the body. Is it that lung qi is too deficient to propel fluids, or is there pathogenic qi obstructing the passage? The wisdom of the ancients in observing the body's functioning may well be hidden in this nasal mucus that "does not take the ordinary road."

II. First Distinguish "Cold, Heat, Deficiency, and Excess": What Constitutional Code Does the Refluxing Mucus Reveal?

Clinical observation has found that postnasal drip is not uncommon among the population, but the underlying constitutional types may be completely different. Some people have refluxing nasal mucus that is thin and clear like water, colorless and transparent; others have mucus that is thick like paste, yellow or white in color; still others feel as though there is a lump of phlegm stuck in the throat that can be neither coughed up nor swallowed down. These differences are precisely the key clues for syndrome differentiation.

From the perspective of disease nature, thin and clear mucus mostly belongs to cold or deficiency, indicating that lung qi is insufficient to secure and retain body fluids, causing the fluids to lose constraint and flow upward instead; thick and sticky mucus mostly belongs to heat or phlegm-dampness, suggesting that damp-heat or phlegm-turbidity is stagnating internally, with turbid yin failing to descend and instead flooding upward. If the color is yellow and the odor is strong, it often points to phlegm-heat accumulating in the lung; if the color is clear-white and the texture is thin, it is mostly related to deficiency-cold of lung qi.

This inevitably makes one reflect: even though both are "postnasal drip," the pathogenesis differs fundamentally in terms of cold, heat, deficiency, and excess, so the treatment principles must also differ. If one only focuses on the phenomenon of "reflux" itself while ignoring the constitutional code behind it, the direction may well be off.

There is also an easily overlooked dimension: the location of the reflux is the throat, which is "the meeting point of all the channels," with multiple meridians passing through it. This means that the root of the problem may not lie solely in the lung, but may also be intricately connected to the transportation and transformation of the spleen and stomach, the warming of kidney yang, and even the soothing and discharging state of liver qi.

III. Spleen Deficiency Generating Phlegm That Floods Up to the Throat: A Common Mechanism of Postnasal Drip

In clinical practice, for a considerable number of people with postnasal drip, the root cause lies in the spleen and stomach rather than the lung. What is the reasoning behind this? The spleen and stomach are the "source of phlegm generation." Food and drink must be transformed and transported by the spleen and stomach before they can become subtle nutrients that nourish the whole body. If the spleen and stomach's transformation and transportation capacity is insufficient, water-dampness will remain and accumulate into phlegm. When phlegm-turbidity floods upward and blocks the nasal passages and throat, symptoms such as postnasal drip and a foreign body sensation in the throat appear.

Such individuals often have irregular eating habits, indulging in raw, cold, greasy foods, or suffer from excessive rumination that impairs the spleen. Their nasal mucus tends to be sticky, with a relatively large amount of phlegm, and may be accompanied by fatigue, weakness, poor appetite, and loose stools. The tongue body often appears enlarged with tooth marks on the edges, and the tongue coating is white-greasy or thick-greasy—these features are quite typical in the four diagnostic methods of Chinese medicine and are key evidence for identifying spleen deficiency with phlegm-dampness.

Therefore, if spleen deficiency with phlegm-dampness is the main contradiction, the core treatment principle is not to "stop the mucus" but to "eliminate the source of phlegm." Once the spleen's transportation function is robust, dampness and turbidity will naturally resolve, and postnasal drip will lose its material basis.

But from another perspective, if the refluxing nasal mucus is thin and clear like water, worsens with cold exposure, and is accompanied by aversion to cold, cold hands and feet, and copious clear urine—is that still spleen deficiency with phlegm-dampness? Probably not necessarily. In such cases, the focus of the problem may need to shift from the "spleen" to the "kidney," and from phlegm-dampness to deficiency-cold.

IV. Kidney Yang Insufficiency with Loss of Containment: Another Syndrome Differentiation Path for Thin, Clear Nasal Mucus

There is a core proposition in TCM theory: "The kidney governs water." The metabolism of body fluids is inseparable from the warming and qi-transforming action of kidney yang. When kidney yang is insufficient, body fluids cannot be normally steamed and vaporized, and they spill out abnormally in various forms. If postnasal drip manifests as thin, non-sticky, copious mucus that worsens with cold, it is often related to kidney yang deficiency and loss of containment—a pattern of "deficiency below with spillage above."

This type of refluxing mucus brings to mind an analogy: when water in a pot boils, steam rises and condenses into water droplets on the lid; if the fire under the stove is not strong enough, the water cannot be vaporized into qi and can only stagnate in low places or overflow. Kidney yang is the fire under the cauldron. When the fire is weak, water metabolism becomes abnormal, and cold qi flooding upward carries body fluids back into the throat.

Such individuals often present with accompanying kidney deficiency manifestations such as soreness and weakness of the lower back and knees, frequent nocturia, and listlessness, with a pale, enlarged tongue and a deep, thin pulse. This leads one to reflect: if clearing heat and resolving phlegm were applied to this situation, it might actually be counterproductive. When the direction is wrong, the harder one pushes, the greater the deviation.

Different pathogenesis corresponds to different constitutions, and constitutions are not fixed—they are jointly influenced by diet, daily routine, emotions, and environment. Therefore, TCM treatment is never a mechanical operation of "one drug for one disease," but rather a dynamic matching of "one syndrome to one method."

V. Chronic Illness Entering the Collaterals and Qi Stagnation: The Subtle Connection Between Emotions and the Meridians

Apart from the spleen, stomach, and kidney, there is another dimension often overlooked: stagnation of qi movement. The Plain Questions·Chapter on the Separation and Union of the Meridians states: "When one falls or is frightened, panting arises from the liver; when one is startled or terrified, panting arises from the lung." Emotional fluctuations directly interfere with the ascending and descending of visceral qi, and the throat happens to be the the necessary path (necessary passage) for the ascent and descent of qi.

People who experience prolonged rumination, anxiety, or suppressed emotions are prone to liver qi depression. The liver governs free coursing and can regulate the movement of qi throughout the body. Once liver qi becomes depressed, the flow of qi is impeded, and the distribution of body fluids is also hindered. If it lodges in the throat, it creates the sensation of "plum-pit qi"; if it lodges in the nasal passages, postnasal drip continues unabated. This type of reflux is often related to emotional fluctuations—worsening with emotional tension and easing with relaxation, and it is frequently accompanied by chest tightness, sighing, and distension in the hypochondriac regions.

This pattern of "qi depression causing mucus to flow upward" reminds us that postnasal drip is not merely a local problem; it is a reflection of the whole body's qi transformation function. If one only looks at the nose and throat, it is like seeing only the trees without seeing the forest. Emotions are an invisible driving force that, by influencing the movement of qi, quietly rewrites the direction of body fluid flow.

Therefore, when observing the state of postnasal drip, one should not only look at the quantity and color of the phlegm and mucus, but also pay attention to its subtle connection with emotions, stress, and the pace of life. This "weather station" is more sensitive than we imagine—it reflects not only the state of the lung, spleen, and kidney, but also the life rhythm of the entire person.

VI. Diet, Daily Routine, and Regulating Qi Movement: A Holistic View of Daily Nurturing

Returning to the classic proposition that "the lung governs nasal mucus," the TCM approach to nurturing always revolves around restoring the dynamic balance of qi movement. Since postnasal drip is related to the coordination of the lung, spleen, kidney, and liver qi, diet and daily routine should conform to the four seasons, protect yang qi, and reduce the sources of phlegm and dampness.

In terms of diet, for those with lung-spleen qi deficiency and predominant phlegm-dampness, it is advisable to eat fewer raw, cold fruits and vegetables as well as sweet, greasy, and heavy-flavored foods, so as to avoid further damaging spleen yang. In terms of daily routine, staying up late most depletes kidney yin, while overexertion most damages spleen yang. A regular schedule is an important cornerstone for maintaining the normal rhythm of body fluid metabolism. Emotional regulation is also an indispensable part—when liver qi is smooth and free, qi movement operates normally, and body fluids can follow their proper pathways. Exercise and guided movements (daoyin) are among the nurturing methods of TCM, but specific plans must be determined by a licensed TCM practitioner based on individual constitution in order to achieve the effects of regulating qi movement and helping transform dampness.

It should be reiterated that in TCM clinical practice, when managing postnasal drip, one must first distinguish whether the main pattern is spleen deficiency with phlegm-dampness, kidney yang insufficiency, or a combination with liver qi depression—the treatment directions for the three differ, and they cannot be generalized. If the refluxing mucus contains blood, or is accompanied by headache, ear fullness, or a marked decrease in smell, it is recommended to seek formal medical facilities for a definitive examination and not to blindly rely on TCM self-treatment.

VII. The Refluxing Nasal Mucus: What Is the Body Trying to Remind Us Of?

From the classic exposition in the Yellow Emperor's Classic of Internal Medicine that "the lung produces nasal mucus" to the multi-viscera differentiation framework involving the lung, spleen, kidney, and liver, postnasal drip—a seemingly inconspicuous symptom—actually implicates the overall picture of the body's qi transformation. It reminds us that every abnormal signal from the body has its origin and its outlet; the key is whether we are willing to pause and listen.

Thin or thick, worsening with cold or heat, with or without phlegm, changing with emotional fluctuations—these subtle differences are all messages written by the body for us. The next time you notice nasal mucus flowing backward, perhaps do not rush to eliminate the symptom, but first observe: When does it occur? Under what conditions does it worsen? And what ways can temporarily alleviate it?

Have you ever considered that postnasal drip may not merely be a local problem of the nasal cavity or throat? It may be the body reminding you—that it is time to re-examine the rhythm of diet, work, and rest; time to pay attention to how emotional stress shapes your body; and time to reflect on what kind of lifestyle truly matches your constitutional endowment. The wisdom of TCM syndrome differentiation begins precisely from this point of awareness.

References:

1. The original text of the Yellow Emperor's Classic of Internal Medicine·Plain Questions can be consulted in the TCM ancient literature database: https://tcmdata.cintcm.com/

2. WHO strategy document on traditional medicine: https://www.who.int/health-topics/traditional-complementary-and-integrative-medicine

3. Official website of the National Administration of Traditional Chinese Medicine: https://www.satcm.gov.cn/

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