1. Prescription Source & History

1. Origin & Development

Pingwei Powder originated from 'Prescriptions of the Taiping Huimin Dispensary' in the Song Dynasty, which is the first official pharmaceutical codex in Chinese history. In the Song Dynasty, medicine developed rapidly and the official management of medicine became more standardized. The appearance of 'Prescriptions of the Taiping Huimin Dispensary' provided a standardized basis for clinical medication. As one of the classic prescriptions in it, the birth of Pingwei Powder is the summary of the long-term clinical practice experience of ancient doctors. Its emergence provided an important basic prescription for treating spleen and stomach diseases in later generations.

Ping Wei San (平胃散), known in English as Calm the Stomach Powder, is a classical TCM formula specifically designed to transform Dampness and regulate the Spleen and Stomach. It is one of the most fundamental formulas for treating patterns of Dampness obstructing the middle jiao, where accumulated Dampness impairs the Spleen’s transforming and transporting functions. It is particularly indicated for poor appetite, abdominal distension and fullness, loose stools, heavy sensation in the limbs, nausea, belching, and a thick greasy white tongue coating. In modern clinical practice, Ping Wei San is widely used as a base formula for various digestive disorders caused by Dampness, including chronic gastritis, functional dyspepsia, and diarrhea with Dampness signs. By powerfully drying Dampness and promoting the smooth movement of Qi in the middle jiao, it restores healthy digestion and appetite.

2. Historical Records & Inheritance

Since the Song Dynasty, Pingwei Powder has been widely used in clinical practice. Many ancient medical books have recorded and discussed it. For example, 'Examination of Medical Prescriptions' in the Ming Dynasty mentioned: 'Pingwei Powder is a balanced prescription for regulating the stomach.' With its definite curative effect, it has been passed down from generation to generation in traditional Chinese medicine clinical practice and has become a commonly used prescription for treating dampness stagnation syndrome of the spleen and stomach. As time goes by, the application scope of Pingwei Powder has been continuously expanded. Not only in China, but also spread to neighboring countries such as Japan and Korea, having a certain impact on the development of medicine in the East Asian region.

2. Composition of Pingwei Powder

1. Monarch Drug - Atractylodes Lancea

Atractylodes lancea is pungent, bitter and warm in nature, belonging to the spleen, stomach and liver meridians. Its pungent, fragrant and dry nature can dry dampness and strengthen the spleen, being the monarch drug in Pingwei Powder. Atractylodes lancea is good at removing dampness pathogens in the spleen and stomach and restoring the transportation and transformation functions of the spleen and stomach. It can dry dampness and promote the transportation of the spleen, enabling the qi of the spleen and stomach to stretch and function normally, thus eliminating symptoms such as abdominal distension and loss of appetite caused by internal obstruction of dampness pathogens.

2. Minister Drug - Magnolia Officinalis

Magnolia officinalis is bitter, pungent and warm in nature, belonging to the spleen, stomach, lung and large intestine meridians. Magnolia officinalis has the effect of promoting qi circulation and drying dampness, and can descend qi to relieve fullness. When combined with Atractylodes lancea, it enhances the effect of drying dampness and promoting qi circulation. The qi-promoting effect of Magnolia officinalis can eliminate the distending pain caused by qi stagnation in the spleen and stomach, and at the same time helps Atractylodes lancea better play the role of drying dampness and strengthening the spleen. The two complement each other and jointly target the pathogenesis of dampness stagnation in the spleen and stomach and qi mechanism disharmony.

3. Assistant Drug - Tangerine Peel

Tangerine peel is pungent, bitter and warm in nature, belonging to the spleen and lung meridians. Tangerine peel has the effects of regulating qi and strengthening the spleen, drying dampness and resolving phlegm. In Pingwei Powder, as an assistant drug, on the one hand, it assists Atractylodes lancea and Magnolia officinalis to enhance the power of drying dampness and promoting qi circulation, and on the other hand, it can regulate qi and harmonize the middle, making the qi of the spleen and stomach smooth. It can relieve symptoms such as nausea and vomiting caused by qi stagnation in the spleen and stomach, and its phlegm-resolving effect also helps to eliminate phlegm caused by dampness pathogens.

4. Messenger Drug - Prepared Licorice Root

Fried licorice is sweet in taste, neutral in nature, belonging to the spleen, stomach, lung and heart meridians. Fried licorice plays the role of harmonizing all the drugs in Pingwei Powder, and at the same time can invigorate the spleen and benefit qi. It can relieve the dry and strong nature of Atractylodes lancea and Magnolia officinalis, making the property of the whole prescription more mild and avoiding being too drastic and damaging healthy qi. In addition, the spleen-strengthening effect of fried licorice also helps to enhance the transportation and transformation functions of the spleen and stomach and promote the recovery of the body.

Pathogenesis, Efficacy and Treatment

1. Analysis of Pathogenesis

The spleen and stomach are the foundation of acquired constitution and are responsible for transporting and transforming water and dampness. If the functions of the spleen and stomach are disordered and dampness pathogens are generated internally, it will lead to abnormal transportation and transformation of the spleen and stomach and disharmony of qi mechanism. When dampness pathogens obstruct internally and the ascending and descending of the spleen and stomach are out of order, symptoms such as abdominal distension, nausea and vomiting, and loss of appetite will occur. The pathogenesis targeted by Pingwei Powder is dampness stagnation in the spleen and stomach and qi mechanism disharmony.

2. Efficacy

Pingwei Powder has the effects of drying dampness and promoting the transportation of the spleen, promoting qi circulation and regulating the stomach. Through the drying dampness effects of drugs such as Atractylodes lancea and Magnolia officinalis, the dampness pathogens in the spleen and stomach are removed; through the qi-promoting effects of Magnolia officinalis and Tangerine peel, the qi mechanism of the spleen and stomach is restored to smoothness; through the harmonizing effect of fried licorice, the whole prescription gives play to the comprehensive effects of drying dampness and promoting the transportation of the spleen, promoting qi circulation and regulating the stomach.

3. Treatment

Pingwei Powder is mainly used to treat the syndrome of dampness stagnating in the spleen and stomach. The clinical manifestations include abdominal distension and fullness, loss of appetite, tastelessness in the mouth, nausea and vomiting, belching and acid regurgitation, heaviness of the limbs, lethargy and inclination to lie down, frequent loose stools, thick and greasy white tongue coating, and a slow pulse. These symptoms are all caused by dampness stagnating in the spleen and stomach. Pingwei Powder can effectively improve these symptoms and restore the normal functions of the spleen and stomach.

IV. Analysis of Pingwei Powder

1. Dry Dampness and Strengthen Spleen

Atractylodes lancea, as the monarch drug, its function of drying dampness and strengthening the spleen is the core of Pingwei Powder. Atractylodes lancea can directly target the dampness pathogen in the spleen and stomach. Through its pungent, aromatic and drying nature, it can remove the dampness pathogen and restore the transportation and transformation functions of the spleen and stomach. Its mechanism of action is to regulate the water metabolism of the spleen and stomach, promote the excretion of dampness pathogen, so that the spleen and stomach can normally transport and transform the essence of food and water.

2. Promote Qi and Remove Fullness

Magnolia officinalis and Citrus reticulata Blanco work synergistically to enhance the effect of promoting qi circulation and relieving fullness. Magnolia officinalis can descend qi and relieve fullness, eliminating the distending pain caused by qi stagnation in the spleen and stomach; Citrus reticulata Blanco can regulate qi and strengthen the spleen, helping to smooth the qi movement. The combination of the two enables the qi of the spleen and stomach to run smoothly, and the symptom of fullness is relieved. This qi-promoting effect can not only improve the symptoms, but also promote the transportation and transformation functions of the spleen and stomach, because the promotion of qi movement can facilitate the transformation of dampness, contributing to the elimination of dampness pathogen.

3. Harmonize Herbs

Fried Licorice Root plays the role of harmonizing all the drugs in the formula. The properties of Atractylodes lancea and Magnolia officinalis are relatively dry and strong. The sweet and slow nature of Fried Licorice Root can moderate their strong nature, making the property of the whole formula more mild and avoiding damage to healthy qi caused by excessive medication. At the same time, Fried Licorice Root can also invigorate the spleen and replenish qi, enhancing the transportation and transformation functions of the spleen and stomach, providing support for the therapeutic effect of the formula.

V. Comparison with Other Similar Formulas

1. Comparison with Huoxiang Zhengqi Powder

Huoxiang Zhengqi Powder also has the effects of relieving exterior syndrome and resolving dampness, regulating qi and harmonizing the middle, which is similar to Pingwei Powder. However, Huoxiang Zhengqi Powder focuses more on the syndrome of exogenous wind-cold and internal injury by dampness stagnation, with the effect of relieving exterior cold, and is applicable to the situation accompanied by exterior syndrome such as aversion to cold and fever. While Pingwei Powder mainly targets the syndrome of dampness stagnating in the spleen and stomach, focusing on drying dampness and promoting the function of the spleen, regulating qi and harmonizing the stomach, without involving relieving exterior syndrome.

2. Comparison with Xiangsha Liujunzi Decoction

Xiangsha Liujunzi Decoction On the basis of Pingwei Powder, drugs such as Aucklandia lappa, Amomum villosum, Codonopsis pilosula, and Atractylodes macrocephala are added, enhancing the effects of strengthening the spleen and replenishing qi, regulating qi and harmonizing the stomach. Xiangsha Liujunzi Decoction is applicable to the situation of qi deficiency of the spleen and stomach combined with qi stagnation and damp obstruction, and it focuses more on the aspect of qi deficiency than Pingwei Powder. Pingwei Powder Primarily targets the syndrome of simple damp stagnation in the spleen and stomach, mainly for drying dampness and promoting qi movement.

VI. Clinical Applications and Indications

1. Digestive System Diseases

Pingwei Powder is widely used in digestive system diseases. For diseases such as chronic gastritis and gastric ulcer, if symptoms of damp stagnation in the spleen and stomach appear, such as abdominal distension, loss of appetite, nausea and vomiting, etc., Pingwei Powder can improve the symptoms and promote the repair of gastric mucosa through the effects of drying dampness and promoting the function of the spleen, regulating qi and harmonizing the stomach. For symptoms such as abdominal distension, belching and acid regurgitation caused by indigestion, gastrointestinal dysfunction, etc., Pingwei Powder also has good curative effects.

2. Skin Diseases

In the field of dermatology, Pingwei Powder also has certain applications. For some skin itching, eczema and other diseases caused by damp heat in the spleen and stomach, Pingwei Powder can relieve skin symptoms by regulating the function of the spleen and stomach and removing damp pathogens in the body. Because damp heat in the spleen and stomach is one of the important reasons for these skin diseases, Pingwei Powder can fundamentally improve the damp heat constitution and achieve the purpose of treating skin diseases.

3. Others

In addition, Pingwei Powder can also be used to treat some other diseases caused by damp stagnation in the spleen and stomach, such as heavy limbs, fatigue and weakness. In the conditioning of some chronic diseases, if there are concurrent syndromes of damp stagnation in the spleen and stomach, Pingwei Powder can also be used as an auxiliary prescription to improve the overall symptoms and enhance the body's disease resistance.

VII. Modified Variations of Pingwei Powder

1. Deficiency-cold of spleen and stomach

If the patient has deficiency-cold in the spleen and stomach, drugs such as dried ginger and Codonopsis pilosula can be added to Pingwei Powder to enhance the effect of warming the middle-jiao and strengthening the spleen. Dried ginger is warm in nature and can warm the middle-jiao and dispel cold, and Codonopsis pilosula replenishes qi and strengthens the spleen. The combination of the two with the original drugs of Pingwei Powder can treat the disease of deficiency-cold in the spleen and stomach combined with damp stagnation.

2. Damp-heat accumulation

If the internal accumulation of damp-heat is more obvious, drugs for clearing heat and drying dampness such as Coptis chinensis and Scutellaria baicalensis can be added. Coptis chinensis and Scutellaria baicalensis are bitter and cold, capable of clearing heat and purging fire, drying dampness and detoxifying. They act synergistically with the dampness-drying drugs in Pingwei Powder to enhance the effect of clearing heat and drying dampness, and are applicable to the syndrome of damp-heat in the spleen and stomach.

3. Qi stagnation and blood stasis

If there are symptoms of qi stagnation and blood stasis, drugs for promoting blood circulation and removing blood stasis such as Ligusticum chuanxiong and Paeonia lactiflora can be added. Ligusticum chuanxiong and Paeonia lactiflora can promote qi and activate blood circulation, improve the condition of qi stagnation and blood stasis, and make qi and blood flow smoothly. They have a good therapeutic effect on the diseases caused by qi stagnation in the spleen and stomach leading to unsmooth qi and blood.

VIII. Dosage (Traditional and Modern Concentrated Granules)

1. Traditional method

The traditional usage is to equally divide Atractylodes lancea, Magnolia officinalis, Citrus reticulata Blanco, and Honey-fried Licorice into four parts and make them into coarse powder. Take two qian each time, add one cup of water, two slices of fresh ginger and two Chinese dates, decoct until seven-tenths, remove the dregs and take it warm, at any time. This traditional decocting and taking method can fully exert the efficacy of the drugs. Through decocting with water, the active ingredients of the drugs are fully dissolved and convenient for the human body to absorb.

2. Modern concentrated granules

Modern concentrated granules are made by extracting and concentrating the drugs of Pingwei Powder into granules. When taking, according to the dosage in the instruction manual, just take it with boiling water. Modern concentrated granules have the advantages of convenient taking and easy storage, and are suitable for the modern fast-paced lifestyle. Their efficacy is basically the same as that of the traditional decoction, but the dosage may be adjusted according to the process. The specific dosage needs to refer to the drug instruction manual.

IX. Precautions and Taboos

1. Use with caution for those with yin deficiency and internal heat

Pingwei Powder has a relatively dry property. Those with yin deficiency and internal heat may aggravate the depletion of yin fluid in the body after taking it, resulting in aggravated symptoms such as dry mouth and throat, and red tongue with little coating. Therefore, it should be used with caution.

2. Caution for Pregnant Women

Although most of the drugs in Pingwei Powder are relatively mild, pregnant women still need to use drugs carefully. Its effect of drying dampness and promoting qi movement may have a certain impact on the fetus. Therefore, pregnant women should use it under the guidance of a doctor.

3. Dietary Taboos

During the period of taking Pingwei Powder, cold, raw, greasy, spicy and other stimulating foods should be avoided. These foods may increase the burden on the spleen and stomach and affect the therapeutic effect of the drugs. At the same time, attention should be paid to the diet rule to maintain the normal transportation and transformation function of the spleen and stomach.

X. Modern Research Progress

1. Research on Pharmacological Effects

Pingwei Powder is a classic prescription in the treatment of the syndrome of dampness stagnating in the spleen and stomach, dampness stagnating in the spleen and stomach, and dampness stagnating in the spleen and stomach in traditional Chinese medicine prescription science. It has the functions of drying dampness and harmonizing the stomach, drying dampness and strengthening the spleen, drying dampness and promoting the transportation of the spleen, regulating qi and harmonizing the stomach, promoting qi and harmonizing the stomach, harmonizing the stomach and descending adverse qi, promoting qi and removing fullness, regulating the spleen and stomach, regulating various drugs, aromatic and bitter drying, dampness transformation, and drying dampness and resolving phlegm. It is mainly used for symptoms such as white and greasy tongue coating, abdominal distension and fullness, tastelessness in the mouth, belching with acid regurgitation, vomiting and nausea, laziness and love of lying down, heavy limbs, and slow pulse. Atractylodes lancea in the prescription is the monarch drug, supplemented by Citrus reticulata Blanco, fresh ginger, Chinese dates, etc., decocted in water for oral administration. Clinically, it is used for chronic gastritis, etc., and is often similar to Buhuanjin Zhengqi Powder, that is, drying dampness and harmonizing the stomach, drying dampness and strengthening the spleen, promoting qi and harmonizing the stomach, tastelessness in the mouth, abdominal distension and fullness, regulating various drugs, fresh ginger, Citrus reticulata Blanco, Atractylodes lancea, Chinese dates, white and greasy tongue coating, slow pulse.

Modern research shows that Pingwei Powder has the effects of regulating gastrointestinal motility, promoting digestive juice secretion, anti-inflammation, and antibacterial. The active ingredients in drugs such as Atractylodes rhizome and Magnolia officinalis can regulate the contraction and relaxation of gastrointestinal smooth muscle and improve gastrointestinal function. At the same time, they can also inhibit the inflammatory reaction of the gastrointestinal tract and have a certain inhibitory effect on gastrointestinal infections. These pharmacological effects provide a scientific basis for the clinical treatment of digestive system diseases with Pingwei Powder.

2. Expansion of Clinical Applications

With the development of modern medicine, the clinical application scope of Pingwei Powder has been continuously expanded. In addition to traditional digestive system diseases, there are also relevant research reports in some neurological diseases, immune system diseases, etc. For example, some studies have found that Pingwei Powder has a certain improvement effect on some neurological symptoms such as insomnia and anxiety caused by spleen and stomach disharmony, which has opened up a new field for the clinical application of Pingwei Powder.

3. Research on Dosage Form Improvement

In order to improve the curative effect and taking convenience of Pingwei Powder, a large number of studies have been carried out on its dosage form improvement in modern times. In addition to the modern concentrated granules mentioned above, there are also attempts to make it into dosage forms such as capsules and dripping pills. While maintaining the drug effect, these new dosage forms further improve the compliance of patients and provide better conditions for the application and promotion of Pingwei Powder.