Herbsmith Rx Ma Zi Ren San is a classical Chinese herbal formula recommended by holistic veterinarians to moisten the intestines, drain heat, promote qi movement, and unblock the bowels in dogs, cats, and horses. Comparable to Apricot Seed and Linum Formula and Hemp Seed Powder, it moistens the intestines, drains heat, promotes the movement of qi, and unblocks the bowels, addressing chronic constipation due to heat binding in the stomach and intestines. A six-herb formula from Zhang Zhong Jing's classical Shang Han Lun, Ma Zi Ren San addresses the pi yue (spleen constraint) pattern in which excess stomach heat dries out the intestinal fluids and constrains the spleen's ability to distribute moisture to the large intestine, producing hard, dry stools and frequent urination as the stomach heat drives fluids out through the urine rather than to the intestines. The formula uses two moist oily seeds (Huo Ma Ren and Xing Ren) to directly restore moisture and lubrication to the dry large intestine, Da Huang to gently purge the dry heat obstruction, Zhi Shi and Hou Po to move the accumulated qi stagnation behind the bowel obstruction, and Shao Yao to nourish the yin and soften the liver to prevent the purgative herbs from further drying the intestinal fluids. Well suited for dogs, cats, and horses presenting with chronic dry constipation from intestinal heat and fluid dryness, characterized by hard, dry, infrequent stools, straining to defecate, frequent or increased urination, a red or dry tongue with a yellow coating reflecting the intestinal heat, and a slippery, rapid, or wiry pulse. Available as a concentrated powder mixed into food; cats and dogs use the Canine Blend, while horses use the Equine/Horse Blend. Dosing varies by species and body weight, and your authorizing veterinarian will provide specific guidance.
VETERINARY AUTHORIZATION REQUIRED: Submit Your Authorization Request or Request a TCVM Telemedicine Consultation
What It Supports
- Intestinal moisture restoration and dry bowel lubrication: Restores moisture and lubrication to the dry large intestine using Huo Ma Ren and Xing Ren, two oily moist seeds that directly lubricate the dry intestinal walls and restore the fluid environment needed for normal bowel transit, addressing the intestinal fluid dryness at the branch of the constipation pattern and providing the direct bowel-moistening action that distinguishes Ma Zi Ren San as a moist-purging formula from the stronger heat-purging formulas that address excess heat obstruction without the moistening strategy.
- Intestinal heat draining and bowel obstruction clearing: Drains the intestinal heat and clears the dry heat obstruction using Da Huang's bitter-cold purgative and heat-clearing action, addressing the accumulated dry heat in the large intestine that is both consuming the intestinal fluids and obstructing the normal bowel transit, using a gentle purging action that addresses the heat obstruction without the strong attacking force of the larger Da Huang doses used for acute excess patterns where the moist-purging strategy of Ma Zi Ren San is not sufficient.
- Qi movement and bowel motility restoration: Promotes the movement of qi and restores bowel motility using Zhi Shi's strong qi-moving and stagnation-dispersing action and Hou Po's qi-descending and abdominal fullness-relieving action, addressing the qi stagnation that has accumulated behind the dry heat bowel obstruction and that perpetuates the constipation by preventing normal peristaltic qi movement through the large intestine even as the heat is being drained and the moisture is being restored by the formula's other herbs.
- Yin nourishment and fluid protection during the purging treatment: Nourishes the yin and protects the intestinal fluids from the purgative and heat-draining herbs using Shao Yao's yin-nourishing and liver-softening action, preventing the formula's Da Huang, Zhi Shi, and Hou Po from further drying the already-depleted intestinal fluids during the treatment course, and softening the liver to prevent liver qi stagnation from adding a secondary qi-constraint component to the constipation pattern alongside the primary intestinal heat and fluid dryness.
TCVM Principles
- Primary action - intestinal heat and fluid dryness correction through the moist-purging and qi-moving strategy of the pi yue (spleen constraint) pattern: Addresses the pi yue (spleen constraint) pattern from Zhang Zhong Jing's Shang Han Lun in which excess stomach heat constrains the spleen's normal fluid-distributing function, diverting intestinal fluids into the urine rather than the large intestine and producing the hard dry stools, straining, and frequent urination of the chronic intestinal heat-dryness constipation pattern. The formula's moist-purging strategy directly addresses both components of the pattern simultaneously: the moist oily seeds (Huo Ma Ren and Xing Ren) restore the intestinal fluid environment at the branch while Da Huang drains the intestinal heat at the root and Zhi Shi and Hou Po move the accumulated qi stagnation, producing a gentler and more fluid-protective purging action than the Cheng Qi Tang formulas that are indicated for acute excess heat obstruction without the fluid dryness component of the pi yue pattern.
- Secondary action - fluid protection and liver softening to prevent purgative injury during chronic treatment: Protects the already-depleted intestinal fluids from the formula's purgative and heat-draining herbs using Shao Yao's yin-nourishing and liver-softening action, ensuring the chronic constipation treatment course does not progressively worsen the fluid dryness it is treating. The inclusion of Shao Yao reflects the classical understanding that the pi yue pattern's fluid dryness makes the patient more vulnerable to purgative injury than an acute excess heat pattern, and that even the gentle moist-purging strategy of Ma Zi Ren San requires a fluid-protective herb to be used safely for the sustained treatment course needed to resolve the chronic intestinal heat-dryness constipation pattern in dogs, cats, and horses.
Available Forms
- Powder - Canine Blend (for dogs and cats): Available in 75 g, 150 g, 500 g, 900 g, and 1200 g sizes; mix into food at the recommended dose for your pet's weight. Cats and dogs both use this blend.
- Powder - Equine/Horse Blend (for horses only): Available in 150 g, 500 g, 900 g, and 1200 g sizes; mix into grain at the recommended dose for your horse.
Suggested Use
For Dogs (Canine Blend Powder):
- Under 30 lbs: ½ tsp twice daily, or as prescribed
- 30-80 lbs: 1 tsp twice daily, or as prescribed
- 80-120 lbs: 1½ tsp twice daily, or as prescribed
- Over 120 lbs: 2 tsp twice daily, or as prescribed
For Cats (Canine Blend Powder): ¼ tsp twice daily, or as prescribed
For Horses (Equine/Horse Blend, 1,000 lb horse): Two tablespoons twice daily for 20 days, then two tablespoons once daily in grain. If the horse initially refuses, start with a small amount mixed into grain and gradually increase until the horse is accustomed to the taste. Most horses will readily accept the herbs in their grain.
Ingredients
Active Ingredients: Huo Ma Ren (Semen Cannabis Sativae), Xing Ren (Semen Pruni Armeniacae), Shao Yao (Radix Paeoniae), Zhi Shi (Fructus Immaturus Citri Aurantii), Hou Po (Cortex Magnoliae Officinalis), Da Huang (Radix et Rhizoma Rhei)
Inactive Ingredient: Flaxseed
VETERINARY AUTHORIZATION REQUIRED: Submit Your Authorization Request or Request a TCVM Telemedicine Consultation
Active Ingredient TCVM Actions
Ma Zi Ren San is a six-herb formula from Zhang Zhong Jing's Shang Han Lun addressing the pi yue (spleen constraint) pattern of chronic intestinal heat-dryness constipation through three coordinated herb groups: a moist-lubricating group that restores fluid to the dry large intestine, a heat-purging and qi-moving group that drains the intestinal heat and moves the accumulated qi obstruction, and a yin-protecting herb that prevents purgative injury to the already-depleted intestinal fluids:
- Huo Ma Ren (Semen Cannabis Sativae) - Hemp Seed / Cannabis Seed: Principal herb; moistens the intestines, nourishes the yin and blood, and unblocks the bowels through lubrication; the primary intestinal-moistening herb of the formula and the herb from which the formula takes its name (ma zi ren means hemp seed), providing the oily moist lubrication that directly restores the fluid environment of the dry large intestine and is the defining characteristic of the formula's moist-purging strategy distinguishing it from the drying heat-purging strategy of the stronger Cheng Qi Tang formulas. Used at the largest proportion in the classical formula to ensure adequate intestinal lubrication as the foundation of the bowel-unblocking strategy.
- Xing Ren (Semen Pruni Armeniacae) - Apricot Kernel / Bitter Apricot Seed: Descends the lung qi, moistens the intestines, and stops coughing and wheezing; the second moist-lubricating seed that provides additional intestinal lubrication alongside Huo Ma Ren and contributes lung qi-descending action that supports the large intestine's normal downward qi movement (the lung and large intestine are paired yin-yang organs whose qi movement is closely coordinated), addressing the lung qi's inability to descend and support large intestine transit that often accompanies the intestinal heat-dryness constipation pattern.
- Shao Yao (Radix Paeoniae) - White Peony Root: Nourishes the yin and blood, softens the liver, and relieves cramping and abdominal discomfort; the yin-protecting and liver-softening herb that prevents the formula's purgative and heat-draining herbs from further injuring the already-depleted intestinal fluids during the sustained treatment course, nourishing the yin and blood to ensure the fluid-restoring action of Huo Ma Ren and Xing Ren is not undermined by the drying nature of Da Huang, and relieving the cramping or abdominal soreness that can accompany both the bowel obstruction and the purgative treatment.
- Zhi Shi (Fructus Immaturus Citri Aurantii) - Immature Bitter Orange Fruit / Unripe Citrus Fruit: Breaks up qi stagnation, reduces accumulation, and relieves abdominal fullness and distension; the primary qi-moving herb that disperses the qi stagnation that has accumulated behind the dry heat bowel obstruction, restoring the normal downward and outward movement of qi through the stomach and large intestine that the constipation has obstructed, and working with Hou Po to fully restore the large intestine's qi dynamic alongside the heat draining and moisture restoration provided by the formula's other herbs.
- Hou Po (Cortex Magnoliae Officinalis) - Magnolia Bark: Promotes the movement of qi, dries dampness, and relieves abdominal fullness and distension; the second qi-moving herb that descends the accumulated qi and relieves the abdominal fullness and distension that accompany the bowel obstruction, working with Zhi Shi to provide comprehensive qi-moving and bowel-motility-restoring action throughout the stomach and large intestine as the intestinal heat is drained and the moisture is restored by the formula's moist seeds and purgative herb.
- Da Huang (Radix et Rhizoma Rhei) - Rhubarb Root and Rhizome: Drains heat, purges accumulation, clears heat from the blood, and invigorates the blood; the heat-draining and gentle-purging herb that addresses the dry-heat intestinal obstruction at the root, clearing the accumulated intestinal heat that is the primary cause of the fluid dryness and bowel obstruction in the pi yue pattern. Used at a proportionally smaller dose than in the acute Cheng Qi Tang formulas for excess heat obstruction, reflecting the pi yue pattern's chronic fluid-dryness context where a gentler purging action is appropriate, and the heavy purging strategy of the Cheng Qi Tang formulas would further injure the depleted intestinal fluids.
Potential Drug Interactions
Ma Zi Ren San contains Da Huang (rhubarb), which has well-documented interactions with several pharmaceutical classes: Da Huang has anticoagulant properties that warrant monitoring in animals on warfarin or other anticoagulant medications; its anthraquinone glycosides can affect the absorption and efficacy of oral medications taken concurrently by altering intestinal transit time; and prolonged use of Da Huang-containing formulas warrants monitoring for electrolyte balance, particularly potassium, in animals on cardiac or diuretic medications. Shao Yao has mild anticoagulant and muscle-relaxant properties that may interact with anticoagulant medications and sedatives. The formula is specifically indicated for the intestinal heat-dryness constipation pattern and is not appropriate for constipation from cold patterns, qi deficiency, blood deficiency, or yin deficiency without active intestinal heat signs; use in cold or deficiency patterns may worsen the underlying condition. Pets on anticoagulant, cardiac, or diuretic medications should discuss this formula with their veterinarian before use, and herb-drug interaction research in dogs, cats, and horses remains limited.
Medication categories warranting extra caution include anticoagulant and antiplatelet medications (Da Huang's and Shao Yao's anticoagulant properties), cardiac medications and digoxin (Da Huang's potential effect on potassium balance), diuretic medications (electrolyte monitoring given Da Huang's laxative action), and any oral medications with narrow therapeutic windows where altered intestinal transit time may affect absorption. Your authorizing veterinarian will determine appropriateness based on your animal's condition, current medications, and whether the presenting constipation pattern is the intestinal heat-dryness pattern for which Ma Zi Ren San is indicated.
VETERINARY AUTHORIZATION REQUIRED: Submit Your Authorization Request or Request a TCVM Telemedicine Consultation
Frequently Asked Questions
What conditions is Ma Zi Ren San used for in TCVM?
In Traditional Chinese Veterinary Medicine, Ma Zi Ren San is indicated for the pi yue (spleen constraint) pattern of chronic constipation in which excess stomach heat dries out the intestinal fluids and constrains the spleen's fluid-distributing function, presenting with hard dry infrequent stools, straining to defecate, frequent or increased urination (as stomach heat drives fluids out through the urine rather than to the large intestine), a dry or red tongue with a yellow coating, and a slippery rapid or wiry pulse. Comparable to Apricot Seed and Linum Formula and Hemp Seed Powder, it is indicated specifically for the chronic intestinal heat-dryness constipation pattern and is not appropriate for acute excess heat obstruction (where the stronger Cheng Qi Tang formulas would be indicated) or constipation from cold, qi deficiency, blood deficiency, or yin deficiency patterns without active intestinal heat signs.
How is Ma Zi Ren San administered to dogs, cats, and horses?
Mix the powder directly into food or grain at the dose recommended for your animal's species and body weight. Dogs and cats use the Canine Blend; horses use the Equine/Horse Blend. Dogs and cats receive the formula twice daily; horses receive two tablespoons twice daily for the first 20 days, then once daily for maintenance. If the horse initially refuses, start with a small amount mixed into grain and gradually increase until the horse is accustomed to the taste. Most horses will readily accept the herbs in their grain. Your authorizing veterinarian will confirm the appropriate dose and schedule and monitor stool consistency, urinary frequency, and tongue quality to track the resolution of the intestinal heat-dryness pattern and determine when to adjust or discontinue treatment.
How long does it take to see results with Ma Zi Ren San?
Because Ma Zi Ren San addresses both the active intestinal heat obstruction and the underlying fluid dryness that the heat has created, response is typically seen relatively quickly in the bowel transit improvement - often within 1 to 2 weeks of consistent use as the intestinal heat is drained and the moisture is progressively restored to the dry large intestine. Stool consistency and urinary frequency typically normalize within 2 to 4 weeks as the pi yue pattern progressively resolves. Your veterinarian will determine the treatment course length based on the degree of intestinal heat and fluid dryness, the animal's constitutional pattern, and whether dietary and environmental factors contributing to the intestinal heat are also being addressed to prevent recurrence.
How does Ma Zi Ren San differ from other TCVM formulas for bowel and digestive conditions?
Ma Zi Ren San is specifically designed for the chronic intestinal heat-dryness constipation pattern (pi yue) and uses a moist-purging strategy that restores intestinal fluid while draining heat, making it distinctly different from other constipation-related formulas. The stronger Da Cheng Qi Tang and Xiao Cheng Qi Tang formulas address acute excess heat obstruction with a forceful purging strategy that is too aggressive for the chronic fluid-dryness pattern and would further injure the depleted intestinal fluids. Run Chang Wan addresses constipation from blood and fluid deficiency without the active intestinal heat component. Formulas for constipation from cold or yang deficiency (such as Ji Chuan Jian) are warm in nature and contraindicated in the heat-dryness pattern. Your authorizing veterinarian will confirm the correct TCVM constipation pattern diagnosis - particularly the presence of hard, dry stools with frequent urination and a yellow tongue coating confirming the intestinal heat-dryness pattern - before selecting Ma Zi Ren San as the appropriate formula.