Ma Zi Ren Wan: A Chinese Herb Medicine for Constipation Relief
- Hongji Medical
- Feb 10
- 6 min read
Chinese Herb Medicine, Ma Zi Ren Wan, also known as Hemp Seed Pill, is a time-honored remedy from traditional Chinese medicine (TCM) designed to relieve constipation by moistening the intestines.
Originating from the Treatise on Febrile Diseases by the renowned physician Zhang Zhongjing in the late Eastern Han Dynasty, this formula was initially called "Pi Yue Wan" to address "Pi Yue" syndrome—constipation caused by spleen deficiency, fluid depletion, and intestinal dryness due to heat in the stomach and intestines.
This article explores the origins, composition, uses, modern applications, and precautions of Ma Zi Ren Wan.
Origins and Background
The Treatise on Febrile Diseases is a cornerstone of TCM, profoundly influencing its development. Ma Zi Ren Wan, one of its prescriptions, targets constipation resulting from dry, heat-laden intestines and insufficient spleen function. By lubricating the intestines and clearing heat, it restores smooth bowel movements, making it a go-to remedy for specific types of constipation in TCM.
Composition of Chinese Herb Medicine Ma Zi Ren Wan
Ma Zi Ren Wan combines several herbs, organized according to TCM’s "monarch, minister, assistant, and envoy" framework:
Monarch (Main Herb): Hemp Seed (Ma Zi Ren)Sweet and neutral, hemp seeds are rich and oily, lubricating the intestines to soften stools and ease bowel movements.
Ministerial Herbs: Rhubarb, Citrus Aurantium, Magnolia OfficinalisThese form a mini-formula akin to Xiao Chengqi Decoction, clearing heat and dryness from the stomach and intestines. Rhubarb acts as a laxative, while Citrus Aurantium and Magnolia Officinalis promote qi flow to relieve intestinal stagnation.
Adjuvant Herb: PeonyPeony nourishes blood and yin, alleviating pain from intestinal dryness and supporting smoother defecation.
Assistant Herb: Apricot KernelApricot kernel enhances lung qi, which indirectly moistens the large intestine, aiding bowel movements.
Auxiliary Ingredient: HoneyHoney enhances the moistening effect of hemp seeds and tempers the strong purgative action of the ministerial herbs, protecting the spleen and stomach.
Addition and subtraction changes
According to different conditions, the composition of Maziren Pills can be modified. For example:
For hemorrhoids, constipation and rheumatism : add peach kernel and angelica root to nourish blood, regulate blood circulation, moisten the intestines and promote bowel movements.
Hemorrhoidal bleeding due to dryness and heat in the gastrointestinal tract : Sophora japonica and Sanguisorba officinalis can be added to cool the blood and stop the bleeding.
For those with severe damage to body fluid caused by dryness and heat : add raw rehmannia, Scrophularia ningpoensis, and Dendrobium can increase fluid and promote bowel movements.
Modifications for Specific Conditions
The formula can be tailored to individual needs:
Hemorrhoids or Constipation with Rheumatism: Add peach kernel and angelica root to nourish blood and promote circulation.
Hemorrhoidal Bleeding from Dryness and Heat: Include Sophora japonica and Sanguisorba officinalis to cool blood and stop bleeding.
Severe Fluid Depletion: Add raw rehmannia, Scrophularia ningpoensis, or dendrobium to boost fluids and support bowel movements.
Indications
Ma Zi Ren Wan treats constipation caused by gastrointestinal dryness, heat, and spleen yin deficiency. Excess heat dries the intestines, hardening stools, while a weakened spleen fails to distribute body fluids, worsening constipation.
This condition, known as "spleen restriction" in TCM, leads to dry, hard stools, frequent urination (as fluids collect in the bladder), a red tongue with a slightly yellow coating, and a rapid pulse.
By lubricating the intestines, clearing heat, and promoting qi flow, Ma Zi Ren Wan effectively relieves constipation and restores normal bowel function.
Efficacy
Ma Zi Ren Wan excels at moistening the intestines, clearing heat, and promoting smooth bowel movements. Its primary herb, hemp seed, softens stools, while the ministerial herbs eliminate stagnation and heat. This makes it ideal for constipation caused by dry, heat-laden intestines, particularly in cases of hard, difficult-to-pass stools.
Modern Applications
In contemporary medicine, Ma Zi Ren Wan is widely used for various constipation issues, including:
Constipation in the elderly or those with weak constitutions.
Habitual constipation.
Postpartum constipation.
Constipation following hemorrhoid surgery.
It also shows promise in managing digestive disorders like irritable bowel syndrome, acid reflux, and enteritis, thanks to its gentle, moisturizing effects.
Precautions
While effective, Ma Zi Ren Wan requires careful use:
Avoid Regular Use in the Elderly or Those with Weak Constitutions: Its purgative herbs may deplete vital energy in frail individuals or those with low blood and fluid levels.
Caution for Pregnant Women: Use only under medical supervision.
Allergy Alert: Avoid if allergic to hemp seeds.
Short-Term Use Only: Prolonged use may lead to dependency or side effects.
Drug Testing Consideration: Hemp seeds may affect urine test results, so avoid use before such tests.
Conclusion
Ma Zi Ren Wan is a powerful TCM remedy for constipation caused by intestinal dryness and heat. By lubricating the intestines, clearing heat, and promoting qi flow, it softens stools and restores healthy bowel function. Widely used in modern medicine for various constipation issues and select digestive disorders, it remains a versatile formula. However, users must heed its precautions to ensure safe and effective use.
Chinese Name | 麻子仁丸 (脾約丸) |
Phonetic | Ma Zi Ren Wan (Pi Yue Wan) |
English Name | Cannabis Fruit Pill (Spleen Confinement Pill) |
Classification | Purgative formulas |
Source | 《Treatise on Cold Damage》Shang Han Lun《傷寒論》 |
Combination | Cannabis Fructus (Ma Zi Ren) 2 sheng (500g), Paeoniae Radix Alba (Shao Yao) 0.5 jin (250g), Aurantii Fructus Immaturus(Zhi Shi) 0.5 jin (250g), Rhei Radix et Rhizoma (Da Huang) 1 jin (500g), Magnoliae Officinalis Cortex (Hou Po) 1 chi (250g), Armeniacae Semen Amarum (Xing Ren) 1 sheng (250g) |
Method | Grind the above medicinals and make them into honey pills. Take 9g of the pills each time with warm water. It can also be prepared as a decoction by adjusting the medicinal quantities based on the original ratio. Mix the decoction with honey. |
Action | Moistens the intestines, drains heat, and moves qi to promote defecation. |
Indication | Ma Zi Ren Wan is indicated for spleen confinement constipation due to dryness-heat in the stomach and intestines. The symptoms are dry stool, frequent urination, a red tongue body, a dry slightly yellow tongue coating, and a rapid pulse. |
Pathogenesis | The pathomechanism is spleen yin deficiency due to dryness-heat in the stomach and intestines. This syndrome was called ”spleen confinement” (pi yue) in the《Treatise on Cold Damage》. “Confinement” means constraint and restriction. The spleen moves the stomach fluid upward and down to spread it to every corner of the body. When there is dryness-heat in the stomach and intestines, spleen yin is damaged. The spleen becomes too dry to move the stomach fluid so the fluids are not able to spread normally. Instead it pours down to the bladder in the form of frequent urination. The loss of moistening and descending within the intestines also causes dry stool because of the confinement. The rapid pulse and red tongue covered by dry, yellow coating are evidence of dryness-heat in the stomach and intestines. The therapeutic principles used to remedy this pattern are to moisten the intestines, drain heat and promote defecation. |
Clarification | 1. Why is xing ren used in this formula to diffuse and descend the lung qi? Given the interior-exterior relation between the large intestine and the lung, the descending and free flowing action of the intestines relies on the diffusing and descending action of the lung qi. If the lung qi can descend and diffuse freely, the intestine will descend and flow freely as well, and the defecation will be normal. This formula promotes defecation by diffusing the lung and descending qi. 2. How is this formula prepared and administered? The purgation should be mild and moistening because the dryness-heat in the stomach and intestines is mild without signs of serious excess such as pi and fullness or distention and pain of the abdomen or stomach cavity. In this scenario the most suitable method of preparation is the honey pill because honey is sweet, moistening, and mild in function. In the original method of administration, only ten pills the size of a parasol tree seed are taken three times per day initially. If the efficacy is not obvious, the dosage can increase until defecation is restored to normal. |
Application | 1. Essential pattern differentiation Ma Zi Ren Wan serves as the common formula used to treat spleen confinement syndrome due to dryness-heat in the stomach and intestines, deficiency of spleen fluid; and, as the representative prescription of the moistening purgative category. This clinical pattern is marked by dry stool, frequent urination, slightly yellow and dry tongue coating. 2. Modern applications This formula may be used in the following biomedically defined disorders when the patient shows signs and symptoms of dryness-heat in the stomach and intestines and fluid consumption: constipation in weak individuals due to intestinal dryness of the aged, habitual constipation, postpartum constipation and hemorrhoids, and postoperative constipation. 3. Cautions and contraindications It is not applicable to the aged, the weak, fluid inadequacy, blood insufficiency, or deficiency spleen and stomach without dryness-heat. Pregnant women should use it with caution. |
Additonal formulae | Wu Ren Wan (Five Kernels Pill, 五仁丸) [Source]《Effective Formulas from Generations of Physicians》Shi Yi De Xiao Fang《世醫得效方》 [Ingredients] Tao ren 1 liang (30g), xing ren 1 liang (30g), song zi ren 1.25 qian (5g), bai zi ren 0.5 liang (15g), yu li ren 1 qian (3g), chen pi 4 liang (crushed separately) (120g) [Preparation and Administration] Grind the five kernels into paste and chen pi into powder, add honey, and make them into pills the size of phoenix tree seed. Take 9g with warm water 1-2 times per day. [Actions] Moistens the intestines to promote defecation. [Applicable Patterns] Deficiency constipation due to fluid exhaustion and intestinal dryness. Symptoms include: dry stool, constipation due to blood deficiency in the elderly and postpartum, a dry tongue with scanty fluid, and a thin, choppy pulse. |
