Yue Bi Jia Zhu Tang (越婢加术汤), known in English as Maidservant from Yue Decoction plus Atractylodes, is a classical TCM formula from the Shang Han Lun for treating Wind-Water (风水) or Wind edema — edema with exterior Wind signs. It is particularly indicated for sudden onset edema with fever, chills, aversion to wind, floating pulse, and difficult urination, often seen in acute nephritis or early stages of fluid retention with exterior invasion. In modern clinical practice, Yue Bi Jia Zhu Tang is used for edema with both exterior Wind-Cold and internal fluid retention. By dispersing the exterior Wind while promoting urination and strengthening the Spleen, it effectively resolves fluid retention with exterior signs.

I. Origins and History

1. Classical Records

Yue Bi Jia Zhu Tang originates from the Jin Gui Yao Lue (Essential Prescriptions of the Golden Cabinet), authored by Zhang Zhongjing of the Eastern Han dynasty. The Jin Gui Yao Lue is China's earliest extant monograph on the diagnosis and treatment of miscellaneous diseases, and has exerted a far-reaching influence on the clinical practice and development of formula studies in later Chinese medicine. In the chapter "Pulse Patterns, Diagnosis, and Treatment of Water-Qi Disease" within the Jin Gui Yao Lue, Yue Bi Jia Zhu Tang is recorded for the first time: "For internal water, Yue Bi Jia Zhu Tang governs it; Gancao Mahuang Tang also governs it." The "internal water" referred to here primarily denotes the oedema condition caused by water-dampness pathogen lodged internally and overflowing into the skin and flesh.

2. Historical Evolution and Transmission

Since the publication of the Jin Gui Yao Lue, Yue Bi Jia Zhu Tang has consistently been valued and applied by physicians of every generation. Over time, later physicians continued to summarise and develop its use in clinical practice. For example, Sun Simiao of the Tang dynasty expanded upon the formula's herb composition and scope of application in the Beiji Qianjin Yaofang (Essential Prescriptions Worth a Thousand Pieces of Gold for Emergencies); the Taiping Huimin Hejiju Fang (Imperial Grace Formulary of the Pharmacy Service) of the Song dynasty standardised aspects of the formula's decoction and administration methods. During the Ming and Qing dynasties, numerous physicians discussed Yue Bi Jia Zhu Tang in greater detail — for instance, Zhang Jingyue provided a more in-depth analysis of its indications in the Jingyue Quanshu (Complete Works of Jingyue), and physicians such as Ye Tianshi accumulated rich clinical experience in its application. This refined and matured the formula's use in treating oedema and related conditions, allowing it to be transmitted from generation to generation and remain widely applied in clinical practice to this day.

II. Herb Composition (Sovereign, Minister, Assistant, Envoy)

1. Chief Herb — Mahuang (Ephedra)

Mahuang is acrid and slightly bitter in flavour and warm in nature, entering the Lung and Bladder channels. Its primary actions are inducing perspiration to release the exterior, diffusing the lungs to calm wheeze, and promoting urination to reduce swelling. In Yue Bi Jia Zhu Tang, Mahuang serves as the chief herb, playing a crucial role. It diffuses lung qi, restoring the lungs' normal diffusing function and thereby promoting fluid metabolism. Through inducing perspiration to release the exterior, the pathogen at the body's surface is resolved through sweating, whilst also assisting the water-dampness pathogen to be expelled through the exterior. For oedema, cough, and wheezing caused by failure of lung qi to diffuse, Mahuang rapidly exerts its therapeutic action, opening the pathway for fluid metabolism and creating the conditions for the other herbs to subsequently exert their effects.

2. Deputy Herb — Shigao (Gypsum)

Shigao is acrid and sweet in flavour and greatly cold in nature, entering the Lung and Stomach channels. It has the actions of clearing heat and draining fire, and generating fluids to relieve thirst. Shigao serves as the deputy herb in the formula, assisting Mahuang in exerting its action. On one hand, Mahuang is warm in nature with a relatively strong diaphoretic potency; for patients with more pronounced interior heat, using Mahuang alone might assist the heat and generate fire. At this point, the cold nature of Shigao restrains Mahuang's warm nature, avoiding the disadvantage of dryness and heat damaging the fluids. On the other hand, Shigao can clear and drain heat from the Lung and Stomach; for patients in whom internally-retained water-dampness has stagnated and transformed into heat, or who already have interior heat, Shigao clears the heat pathogen from the body, allowing the heat to be cleared and the water-dampness pathogen to be more readily expelled. Acting synergistically with Mahuang, the two together achieve the goal of treating oedema with concurrent interior heat.

3. Assistant Herbs — Baizhu (Atractylodes Rhizome), Shengjiang (Fresh Ginger) and Dazao (Jujube)

Baizhu is sweet and bitter in flavour and warm in nature, entering the Spleen and Stomach channels. It has the actions of strengthening the spleen and boosting qi, and drying dampness and promoting urination. As an assistant herb, Baizhu reinforces the spleen-strengthening function of transforming and transporting water-dampness. The body's fluid metabolism is closely related to the transforming and transporting function of the spleen and stomach; when the spleen and stomach function vigorously, water-dampness can be normally transformed and transported and is less likely to accumulate. Baizhu helps to transform and transport the water-dampness pathogen within the body, preventing further overflow of water-dampness and addressing the root cause of oedema.

Shengjiang is acrid in flavour and slightly warm in nature, entering the Lung, Spleen, and Stomach channels. It has the actions of releasing the exterior and dispersing cold, warming the middle to stop vomiting, and transforming phlegm to relieve cough. In the formula, Shengjiang both assists Mahuang in inducing perspiration to release the exterior and warms the stomach to disperse cold, harmonising the middle and directing counterflow downward. It reinforces the formula's exterior-releasing potency, and for patients with spleen-stomach deficiency-cold caused by internally-retained water-dampness presenting with nausea and vomiting, Shengjiang warms the stomach to stop vomiting, harmonising spleen-stomach function and ensuring free movement of middle-burner qi, thereby assisting the transformation and transport of water-dampness.

Dazao is sweet in flavour and warm in nature, entering the Spleen, Stomach, and Heart channels. It has the actions of tonifying the middle and boosting qi, nourishing blood and calming the spirit, and moderating the nature of other medicinals. As an assistant herb, Dazao on one hand tonifies the middle and boosts qi, strengthening spleen-stomach function, and works synergistically with Baizhu to reinforce the spleen-strengthening and water-transforming potency; on the other hand, Dazao moderates the potent nature of Mahuang, Shigao, and the other herbs, making the medicinal nature of the entire formula more balanced, reducing the irritation of the herbs on the body, and protecting the righteous qi.

4. Envoy Herb — Gancao (Licorice Root)

Gancao is sweet in flavour and neutral in nature, entering the Heart, Lung, Spleen, and Stomach channels, with the actions of tonifying the spleen and boosting qi, moistening the lungs to relieve cough, clearing heat and resolving toxicity, and harmonising all the herbs. In Yue Bi Jia Zhu Tang, Gancao serves as the envoy herb, performing the role of harmonising all the herbs. It coordinates the medicinal nature of each herb in the formula, allowing Mahuang, Shigao, and the others to work together and achieve the optimal therapeutic effect. Simultaneously, Gancao also has the action of tonifying the spleen and boosting qi, which strengthens spleen-stomach function and promotes fluid metabolism, while also relieving the irritation of the herbs on the gastrointestinal tract, protecting the spleen-stomach qi, and making the medication process more comfortable for the patient.

III. Pathomechanism, Actions, and Indications

1. Pathomechanism Analysis

The pathomechanism targeted by Yue Bi Jia Zhu Tang is primarily internally-retained water-dampness with concurrent interior heat. The body's lungs govern the regulation of the water passageways; if the lungs lose their diffusing and descending function, fluids cannot be normally distributed and excreted, leading to internally-retained water-dampness that overflows into the skin and flesh, manifesting as oedema. When water-dampness pathogen stagnates and transforms into heat over time, or when the patient already has an underlying interior heat constitution, a pathological state forms in which water-dampness and interior heat become mutually bound. At this point, simply promoting urination and dispelling dampness may fail to resolve the root problem; clearing and draining interior heat on the foundation of diffusing the lungs and disinhibiting water is required to achieve the therapeutic goal.

2. Actions

Yue Bi Jia Zhu Tang has the actions of inducing perspiration to disinhibit water, and clearing heat to relieve vexation. Through Mahuang diffusing lung qi and inducing perspiration to release the exterior, the water-dampness pathogen is expelled through the skin's surface; Baizhu strengthens the spleen, dries dampness, and promotes urination, fundamentally reinforcing the spleen-stomach's function of transforming and transporting water-dampness; Shigao clears and drains heat from the Lung and Stomach, removing the interior heat pathogen from the body; Shengjiang, Dazao, and Gancao harmonise the spleen and stomach and assist the other herbs in exerting their effects. Together they achieve the effect of inducing perspiration to disinhibit water and clearing heat to relieve vexation, allowing the water-dampness to be expelled and the interior heat to be cleared, thereby relieving oedema and related conditions.

3. Indications of the Yuebi Formula

Yue Bi Jia Zhu Tang is primarily used to treat the pattern of wind-water with concurrent heat. Clinical manifestations include eyelid swelling, followed by swelling spreading to the limbs and the entire body, with rapid onset, frequently accompanied by aversion to cold, fever, soreness of the joints, and inhibited urination. In those leaning toward wind-heat, accompanying symptoms include redness, swelling, and pain of the throat, a red tongue, and a floating, slippery, and rapid pulse; in those leaning toward wind-cold, accompanying symptoms include pronounced aversion to cold, cough and wheezing, a thin white tongue coating, and a floating slippery or floating tight pulse. In addition, for symptoms such as skin itching, generalised heat, and thirst caused by internally-retained water-dampness stagnating and transforming into heat, Yue Bi Jia Zhu Tang may also be used for treatment when the presentation corresponds to the above pathomechanism.

IV. Formula Analysis

1. The Mahuang–Shigao Combination

The pairing of Mahuang and Shigao is the key herb combination in Yue Bi Jia Zhu Tang. Mahuang is warm in nature, primarily inducing perspiration to release the exterior and diffusing the lungs to calm wheeze, serving as a potent agent for inducing perspiration and disinhibiting water; Shigao is cold in nature, primarily clearing heat, draining fire, generating fluids, and relieving thirst. The two — one warm, one cold — combined together: with Shigao, Mahuang diffuses the lungs without assisting heat; with Mahuang, Shigao clears heat without cold-suppressing. This combination both fully realises Mahuang's action of diffusing the lungs and disinhibiting water and restrains its warm nature, avoiding dryness and heat damaging the fluids; simultaneously, Shigao's heat-clearing action removes the interior heat pathogen from the body, allowing Mahuang's diaphoretic and water-disinhibiting potency to act more effectively on the water-dampness pathogen, achieving the goal of resolving both exterior and interior and clearing heat whilst disinhibiting water.

2. Synergistic Action of Baizhu with Mahuang and Shigao

Baizhu strengthens the spleen, dries dampness, and promotes urination; Mahuang diffuses the lungs and disinhibits water. The two act synergistically, reinforcing the action of disinhibiting water and reducing swelling. Baizhu, through strengthening the spleen and transforming and transporting, gives the water-dampness pathogen an exit route; Mahuang, through diffusing lung qi, opens the pathway of fluid metabolism, promoting the expulsion of water-dampness from the body. Shigao clears and drains interior heat, preventing the water-dampness pathogen from stagnating and transforming into heat over time, whilst also helping to improve oedema symptoms caused by interior heat. Together with Baizhu and Mahuang, it jointly regulates the body's fluid metabolism, allowing the water-dampness to be expelled and the interior heat to be cleared, achieving the therapeutic effect for oedema with concurrent interior heat.

3. Shengjiang, Dazao and Gancao Harmonising All the Herbs

Shengjiang assists Mahuang in inducing perspiration to release the exterior, warms the stomach to disperse cold, and harmonises the middle whilst directing counterflow downward; Dazao tonifies the middle, boosts qi, and moderates the nature of the herbs; Gancao harmonises all the herbs and tonifies the spleen to boost qi. These three herbs work together, harmonising the medicinal nature of each herb in the formula, making the medicinal nature of the entire formula more balanced — both reinforcing the therapeutic effect of the herbs and reducing their irritation to the body. They also regulate spleen-stomach function and promote fluid metabolism, acting synergistically with the other herbs to jointly exert the therapeutic effect, ensuring the patient's comfort and safety throughout the course of medication.

V. Comparison with Related Formulas

1. Comparison with Gancao Mahuang Tang

Gancao Mahuang Tang originates from the Jin Gui Yao Lue and is composed of just two herbs — Gancao and Mahuang. Its primary action is inducing perspiration to disinhibit water, indicated for "internal water, generalised facial and bodily yellow swelling, a sunken pulse, and inhibited urination." Compared with Yue Bi Jia Zhu Tang, Gancao Mahuang Tang has a simpler herb composition, focusing solely on inducing perspiration to disinhibit water without a heat-clearing action. Yue Bi Jia Zhu Tang, building upon inducing perspiration to disinhibit water, adds Shigao to clear heat, Baizhu to strengthen the spleen and dry dampness, and Shengjiang, Dazao, and Gancao to harmonise all the herbs — making it more suitable for conditions of internally-retained water-dampness with concurrent interior heat. Therefore, Gancao Mahuang Tang is inclined toward treating oedema from simple internally-retained water-dampness, whereas Yue Bi Jia Zhu Tang places greater emphasis on treating oedema conditions accompanied by interior heat.

2. Comparison with Mahuang Lianqiao Chixiaodou Tang

Mahuang Lianqiao Chixiaodou Tang also originates from the Jin Gui Yao Lue, used to treat "cold damage with stasis-heat lodged internally, the body must develop jaundice," with the actions of releasing the exterior, clearing heat, draining dampness, and reducing jaundice. This formula is composed of Mahuang, Lianqiao (Forsythia Fruit, or Forsythia root may also be used), Xingren (Apricot Kernel), Chixiaodou (Red Adzuki Bean), Dazao, raw Zibaipi (Catalpa Bark, or Sangbaipi/Mulberry Root-bark may be substituted), Shengjiang, and Gancao. Compared with Yue Bi Jia Zhu Tang, Mahuang Lianqiao Chixiaodou Tang places greater emphasis on clearing heat, draining dampness, and reducing jaundice, primarily used to treat damp-heat jaundice. Yue Bi Jia Zhu Tang, by contrast, focuses on inducing perspiration to disinhibit water and clearing heat to relieve vexation, primarily targeting oedema from the wind-water pattern with concurrent heat. The two differ markedly in their actions and indications, and accurate pattern differentiation according to the specific condition is required for clinical application.

VI. Clinical Applications

1. Acute Glomerulonephritis

Acute glomerulonephritis is mostly caused by externally-contracted wind pathogen and damp-heat toxin invading internally into the Lung and Spleen, causing the lungs to lose their regulating function, the spleen to lose its transforming and transporting function, water-dampness to be retained, and overflow into the skin and flesh, giving rise to the disease. Its clinical manifestations often correspond to the wind-water pattern with concurrent heat — such as eyelid swelling rapidly spreading throughout the body, accompanied by fever, sore throat, and inhibited urination. Yue Bi Jia Zhu Tang has the actions of inducing perspiration to disinhibit water and clearing heat to relieve vexation, effectively resolving the exterior pathogen, diffusing the lungs and disinhibiting water, and clearing the damp-heat pathogen from the body, producing good therapeutic results for the early-stage treatment of acute glomerulonephritis. In clinical application, modifications may be made according to the patient's specific symptoms — for example, Jinyinhua (Honeysuckle Flower) and Lianqiao (Forsythia Fruit) may be added for pronounced sore throat to clear heat, resolve toxicity, and benefit the throat; Fuling (Poria) and Zexie (Alisma Rhizome) may be added for severe oedema to reinforce the water-disinhibiting and swelling-reducing potency.

2. Acute Exacerbation of Chronic Glomerulonephritis

In patients with chronic glomerulonephritis, if an acute exacerbation is triggered during the remission phase by factors such as externally-contracted pathogen, symptoms of wind-water with concurrent heat may also appear, in which case Yue Bi Jia Zhu Tang is equally applicable. Patients with chronic glomerulonephritis typically have insufficient righteous qi and spleen-kidney deficiency with internally-retained water-dampness; upon contracting wind pathogen or damp-heat pathogen, the interior and exterior pathogens combine, causing acute worsening of the condition. Yue Bi Jia Zhu Tang can expel the pathogen while simultaneously supporting the righteous, improving the patient's oedema and fever symptoms through inducing perspiration to disinhibit water and clearing heat to relieve vexation, thereby controlling disease progression. In application, Huangqi (Astragalus Root) and Dangshen (Codonopsis Root) may be appropriately added according to the patient's constitution and condition to strengthen the spleen and boost qi, reinforcing the body's resistance and promoting recovery.

3. Oedema Phase of Nephrotic Syndrome

Patients with nephrotic syndrome commonly present with marked oedema, with the pathomechanism mostly involving spleen-kidney deficiency and overflow of water-dampness. During the oedema phase, if accompanied by externally-contracted wind-heat pathogen or interior accumulation of damp-heat, manifestations of wind-water with concurrent heat may appear. Yue Bi Jia Zhu Tang can diffuse the lungs, disinhibit water, clear heat, and drain dampness, having a certain effect in relieving the oedema symptoms of nephrotic syndrome patients. Simultaneously, taking into account the overall pathomechanism of nephrotic syndrome, kidney-tonifying and spleen-strengthening herbs such as Shanyao (Dioscorea Rhizome), Qianshi (Euryale Seed), and Tusizi (Cuscuta Seed) may be added to the formula to treat both root and manifestation. Clinical practice has observed that combining Yue Bi Jia Zhu Tang with Western medication to treat the oedema phase of nephrotic syndrome can improve therapeutic efficacy, reduce recurrence of oedema, and shorten the disease course.

4. Pruritic Skin Conditions

The onset of pruritic skin conditions is associated with multiple factors, among which internally-retained water-dampness stagnating and transforming into heat is a common pathomechanism. Patients typically present with skin itching, with skin flushing visible after scratching, accompanied by symptoms such as generalised heat and thirst. The actions of Yue Bi Jia Zhu Tang in inducing perspiration to disinhibit water and clearing heat to relieve vexation can expel the water-dampness pathogen from the body and clear the interior heat, thereby relieving symptoms of skin itching. For such patients, Difuzi (Kochia Fruit), Baixianpi (Dictamnus Root-bark), and Kushen (Sophora Root) may be added to the base formula to dispel wind and relieve itching, reinforcing the anti-pruritic effect. Clinical application has found that Yue Bi Jia Zhu Tang with modifications can effectively improve symptoms in patients with pruritic skin conditions and improve quality of life.

VII. Clinical Modifications

1. Pronounced Oedema

Water-disinhibiting and dampness-percolating herbs such as Fuling (Poria), Zexie (Alisma Rhizome), and Zhuling (Polyporus) may be added to reinforce the water-disinhibiting and swelling-reducing action. Fuling is sweet and bland in flavour and neutral in nature, entering the Heart, Lung, Spleen, and Kidney channels, with the actions of disinhibiting water and percolating dampness, strengthening the spleen, and calming the heart; Zexie is sweet and bland in flavour and cold in nature, entering the Kidney and Bladder channels, capable of disinhibiting urination and clearing damp-heat; Zhuling is sweet and bland in flavour and neutral in nature, entering the Kidney and Bladder channels, with the action of disinhibiting water and percolating dampness. Combined with Baizhu, these three herbs reinforce the spleen-strengthening and water-disinhibiting potency, allowing the oedema to subside more quickly.

2. Predominant Wind-Heat

Jinyinhua (Honeysuckle Flower), Lianqiao (Forsythia Fruit), and Niubangzi (Burdock Fruit) may be added to clear heat, resolve toxicity, and disperse wind-heat. Jinyinhua is sweet in flavour and cold in nature, entering the Lung, Heart, and Stomach channels, with the actions of clearing heat, resolving toxicity, and dispersing wind-heat; Lianqiao is bitter in flavour and slightly cold in nature, entering the Lung, Heart, and Small Intestine channels, capable of clearing heat, resolving toxicity, reducing swelling, dissipating binds, and dispersing wind-heat; Niubangzi is acrid and bitter in flavour and cold in nature, entering the Lung and Stomach channels, capable of dispersing wind-heat, diffusing the lungs to vent rashes, and resolving toxicity to benefit the throat. These herbs reinforce the formula's heat-clearing and wind-dispersing potency, more effectively treating symptoms such as sore throat and fever caused by predominant wind-heat.

3. Predominant Wind-Cold

Guizhi (Cinnamon Twig) and Fangfeng (Siler Root) may be added to dispel wind and disperse cold. Guizhi is acrid and sweet in flavour and warm in nature, entering the Heart, Lung, and Bladder channels, with the actions of inducing perspiration to release the muscles, warming and unblocking the channels, and assisting yang to transform qi; Fangfeng is acrid and sweet in flavour and slightly warm in nature, entering the Bladder, Liver, and Spleen channels, capable of dispelling wind and releasing the exterior, overcoming dampness and relieving pain, and stopping spasm. The two reinforce the formula's wind-dispelling and cold-dispersing action, suitable for patients with predominant wind-cold and pronounced symptoms such as severe aversion to cold and cough with wheezing.

4. Concurrent Blood Stasis

Yimucao (Motherwort), Zelan (Bugleweed), and Chishao (Red Peony Root) may be added to activate blood and resolve stasis. Yimucao is acrid and bitter in flavour and slightly cold in nature, entering the Heart, Liver, and Bladder channels, with the actions of activating blood and regulating menstruation, promoting urination and reducing swelling, and clearing heat and resolving toxicity; Zelan is acrid and bitter in flavour and slightly warm in nature, entering the Liver and Spleen channels, capable of activating blood and resolving stasis, and moving water and reducing swelling; Chishao is bitter in flavour and slightly cold in nature, entering the Liver channel, with the actions of clearing heat and cooling blood, and dispersing stasis to relieve pain. These herbs can address blood stasis symptoms concurrently while treating oedema, promoting blood circulation and improving the condition.

VIII. Dosage and Preparation

1. Traditional Method

2. Modern Concentrated Granules

With the development of modern pharmaceutical technology, Chinese herbal medicine is also available in concentrated granule form. For Yue Bi Jia Zhu Tang concentrated granules, administration generally follows the product instructions, with each dose equivalent to one-half to a full traditional dose, taken in 1 to 3 administrations; the specific dosage should follow the product instructions or medical guidance. Concentrated granules are convenient to carry and store, and should be dissolved in warm boiled water at the time of administration. Pregnant women, those with weak constitutions, and those with serious underlying conditions should use this formula under medical guidance.

IX. Precautions and Contraindications

1. Precautions for Concurrent Medication

When using this formula concurrently with Western medication, the attending physician should be informed to avoid interactions with diuretics, cardiotonic drugs, and similar medications. Preparations containing Mahuang should be used with caution alongside stimulants and antihypertensive medications, with monitoring of heart rate and blood pressure changes.

2. Monitoring During Treatment and Discontinuation Principles

During the course of medication, body weight, urine output, the degree of swelling, and changes in heat signs should be monitored. If symptoms show marked improvement, the medication should be gradually discontinued or switched to a righteous-supporting and dampness-transforming formula under medical guidance; if the condition worsens or marked adverse reactions appear, the medication should be discontinued immediately and medical attention sought.

X. Modern Research

1. Pharmacological Evaluation

Yue Bi Jia Zhu Tang originates from the Jin Gui Yao Lue and is formed from the Yuebi Tang formula with the addition of Baizhu, primarily indicated for water-qi diseases such as wind-water with aversion to wind and generalised swelling, and is applicable for acute nephritis, allergic skin disease, and epidemic haemorrhagic fever, among other conditions. Those for whom Yuebi Tang is indicated have no marked heat, with continuous spontaneous sweating, the formula serving to diffuse and release the spleen qi; Fuzi (Aconite) may be clinically added to warm yang, and patients commonly present with aversion to wind and a floating pulse.

Regarding the toxicity and adverse reactions of constituents such as Mahuang within Yue Bi Jia Zhu Tang, research recommends strictly controlling the dosage, limiting the duration of continuous use, and exercising caution in patients with cardiovascular disease, pregnant women, and elderly patients with comorbidities, in order to improve safety.

2. Directions for Multidisciplinary Collaborative Research

Future research directions include establishing standardised clinical pathways, conducting multi-centre randomised controlled trials to verify efficacy, elucidating the molecular mechanisms of the primary active constituents, and optimising dosage forms and administration regimens, in order to advance the standardised application of Yue Bi Jia Zhu Tang within the modern healthcare system.