The term ‘purisha’ means fecal matter or stool. It denotes the waste product or undigested residue remaining after the nutrient fraction of the food has been separated and absorbed. The feces (purisha) are important for normal physiological functions of vayu and agni. (SAT-B.459). Stool examination is an important test for assessment of status of digestion and overall health. This article deals with physiological, pathological, diagnostic and therapeutic aspects of stool.
|Section/Chapter/topic||Sharira / Mala /Purisha|
|Authors||Anagha S., Deole Y.S.|
|Reviewer and Editor||Basisht G.|
|Affiliations||Charak Samhita Research, Training and Development Centre, I.P.G.T.& R.A., Jamnagar|
|Publisher||Charak Samhita Research, Training and Development Centre, I.T.R.A., Jamnagar, India|
|Date of first publication:||January 8, 2021|
Meaning and synonyms
The Sanskrit word ‘purisha’ is derived from root “pru” by adding the suffix “ishan” that means crumbling or loose earth, excremental dirt, rubbish, the solid mass which fills up (the intestine) etc. It is also known by synonyms like shakrut, varcha/varchaska, vishtha and vit in Sanskrit literature.
Fundamental composition and properties
Fresh faeces contain around 75% water and the remaining 25% solid. The solid fraction is 84–93% organic which contains:
- bacterial biomass - 25–54%
- nitrogenous matter- 2–25%
- carbohydrate or undigested plant matter -25%
- fat- 2–15%
- Other constituents- calcium and iron phosphates, intestinal secretions, small amounts of dried epithelial cells, and mucus.
When the food material from the stomach (amashaya) reaches the large intestine (pakwashaya), it is dried up by the heat of pitta and absorbing property (ruksha guna) of vata to form lumps. [Cha. Sa. Chikitsa Sthana 15/11] Defecation is regulated by vata dosha.
The physiology of stool formation and defecation in described as follows.
Feces formation takes place in the large intestine.It carries out functions like absorbing water and electrolytes, forming and propelling feces toward the rectum for elimination. Most nutrients and up to 90% of the water are absorbed by the small intestine from the indigestible material.The ascending colon absorbs remaining water and other key nutrients from it to form solidified stool.The feces are stored in descending colon and are emptied into the rectum.The sigmoid colon contracts to increase the pressure inside the colon, causing the stool to move into the rectum. The rectum holds the feces awaiting elimination by defecation.
The total quantity of purisha is seven anjali (personified measurement unit).[Cha. Sa. Sharira Sthana 7/15]
On average humans eliminate 128 g of fresh feces per person per day.
It carries the solid waste products of metabolism and helps in preservation of health. It also helps to maintain the microbial flora of intestine.
Channels carrying feces (purishavaha srotas)
The channels carrying feces, are originated from the colon and anorectal region.[Cha.Sa.Vimana Sthana 5/8] [Su. Sa. Sharira Sthana 9/12] The large intestine and rectum form, store and carry fecal matter.
Purishadhara kala (layer forming stools)
Kala means the layer in body observed in sagittal section. The layer holding fecal matter(purishadhara kala) is present inside large intestine (pakwashaya) separates the waste products from the digested food.It covers the alimentary tract, liver and intestine especially in the caecum (unduka).[Su. Sa. Sharira Sthana 4/16-17] This layer performs functions of absorption of nutrients and elimination of harmful substances through stools.
Causes of vitiation
The channels carrying feces are afflicted due to suppression of urge of defecation, over eating, eating during indigestion, especially in persons with poor digestive capacity and who are emaciated. [Cha.Sa.Vimana Sthana 5/21]
The increase or decrease in quality and/or quantity of fecal matter can lead to various abnormal conditions. The states can be assessed by following clinical features.
|Decrease of fecal matter (purisha khaya)*||Increase in fecal matter (purisha vrudhi)**|
|Painful peristalsis in the intestine which spreads upwards and oblique, causing distension of belly and dryness||Gurgling noise in the abdomen|
|Discomfort in the area of heart and flanks (hrudaya- parshwa peeda)||Pain in abdomen|
|Intestinal gas /flatus moving upward along with sound||--|
|Frequent movement of gas in alimentary canal especially at epigastric region||--|
- *[Cha Sa. Sutra Sthana 17/70], [Su. Sa. Sutra Sthana 15/11]
- **[Su. Sa. Sutra Sthana 15/15]
Clinical features of vitiation of channels carrying fecal matter
Difficulty in evacuating bowels, scanty stools, passage with sound and pain, loose motions, or irritable/irregular bowels are observed due to affliction of channels carrying fecal matter.[ Cha. Sa. Vimana Sthana 5/8].
Abdominal distension, excessive foul smell of feces, hardness of bowel or presentations like paralytic ileus are also seen.[Su. Sa. Sharira Sthana 9/12]
Clinical features of suppression of urge of defecation:
- Colic pain
- retention of fecal matter and flatus
- cramps in the calf muscles
- distension of abdomen [Cha. Sa. Sutra Sthana 7/8]
Stool examination(purisha pareeksha)
Examination of feces is included in the eight fold clinical diagnostic methods (ashtavidha pareeksha) mentioned in Ayurveda. [ Sha.Sa. Y.R. malapariksha 1] It is done in various medical conditions.
a) Colour: human feces normally has a light to dark brown colour
The Bristol stool scale is a diagnostic medical tool designed to classify the form of human feces . It is used in both clinical as well as experimental fields.
The seven categories in Bristol Stool Scale. 
|Type 1||Separate hard lumps, like nuts (difficult to pass and can be black)||Constipation|
|Type 2||Sausage-shaped, but lumpy||Constipation|
|Type 3||Like a sausage but with cracks on its surface (can be black)||normal|
|Type 4||Like a sausage or snake, smooth and soft (average stool)||normal|
|Type 5||Soft blobs with clear cut edges||lack of dietary fibre|
|Type 6||Fluffy pieces with ragged edges, a mushy stool||diarrhoea|
|Type 7||Watery, no solid pieces, entirely liquid||diarrhoea|
Feces possesses a physiological odor, which can vary according to diet and medical conditions. Hydrogen sulfide is the main volatile compound in feces.
Occult Blood Test
This test checks for hidden (occult) blood in the feces which is not visible to naked eyes. It detects the subtle blood loss in the gastrointestinal tract, anywhere from the mouth to the colon. It is used in the diagnosis of various conditions starting from peptic ulcer to malignancy like colorectal cancer.
Parasitic diseases such as ascariasis, hookworm etc. can be diagnosed by examining feces under the microscope for the presence of worm larvae or eggs.
Fecal fat test:
It is used as diagnostic test to detect the excess fat in the feces (steatorrhea) indicating fat malabsorption conditions. The dietary fat (primarily triglycerides) is digested by enzymes such as pancreatic lipase in the duodenum, and absorbed in the jejenum of the small intestine.The free fatty acids enter circulation for metabolism and storage.Human feces normally contains very little undigested fat.
Steatorrhea is observed in following conditions:
- Disorders of exocrine pancreatic function, such as chronic pancreatitis, cystic fibrosis and Shwachman–Diamond syndrome (these are characterized by deficiency of pancreatic digestive enzymes)
- celiac disease (in which the fat malabsorption in severe cases is due to inflammatory damage to the integrity of the intestinal lining)
- short bowel syndrome (in which much of the small intestine has had to be surgically removed and the remaining portion cannot completely absorb all of the fat).
- small bowel bacterial overgrowth syndrome.
Assessment of dosha predominance from the characteristic features of stool
|Dosha predominance||Characteristics of stool*|
|Vata||Hard, dry, broken, frothy, dry and smoky color|
|Pitta||Yellowish in color|
|Kapha||Whitish in color|
|Vata-kapha||Brownish in color|
|Pitta- vata||Binding or broken type, yellowish or yellowish black in color|
|Kapha-pitta||Yellowish, white, sticky/slimy|
|Tridosha||Blackish, broken, compact and whitish|
- [Y. R. mala pariksha /1-3]
Sink test for presence of undigested state (sama and nirama avastha):
The stool formed due to improper digestion of food is sticky and sinks into water. The fecal matter well formed after proper digestion floats in water. This test is performed for assessment of digestive status.[Cha. Sa. Chikitsa Sthana 15/ 94]
Bad prognostic features of stool
Excessively blackish/whitish/yellowish/ reddish coloration of feces, excessively hot nature (causing burning sensation in anus), excessively foul-smelling or with a mixture of different colors is indicative of bad prognosis of a disease or imminent death of the person. [Y. R. mala pariksha / 7, 10]
These features are indicative of grave underlying pathologies like gastrointestinal bleeding.
Role of feces in etiopathogenesis and clinical features of diseases
- Suppression of urge of defecation is a causative factor for endogenous generalized edema(shopha)[Cha.Sa.Sutra Sthana 18/ 6], abdominal lump(gulma)[Cha. Sa.Nidana Sthana 3/6], progressive wasting disease(shosha)[Cha.Sa.Nidana Sthana 6/6] etc.
- Suppression of the urge of defecation is one of six types of udavarta (disease due to reverse movement of vata) [ Cha.Sa. Sutra Sthana 19/3]
- Among the 20 types of parasites (krimi), six originate from the faeces. [Cha. Sa. Sutra Sthana 19/4].
- Reduced urge of defecation and retention of stool are prodromal symptoms of abdominal lumps(gulma).[Cha.Sa.Nidana Sthana 3/15]
- Accumulation of feces is a prodromal symptom of generalized enlargement of abdomen(udara)[Cha.Sa.Chikitsa Sthana 13/18]
- Obstructed feces is an important clinical feature of hemorrhoids (arsha).[Cha.Sa.Chikitsa Sthana 14/8]
- The fecal matter is a source of strength(bala) in person suffering from progressive wasting disease (shosha) and tuberculosis (rajayakshma). Excessive elimination of feces through panchakarma is contraindicated in these patients, as it further decreases strength. [Cha.Sa.Nidana Sthana 6/10].[Cha.Sa.Chikitsa Sthana 8/42]
- Loose motions, stool associated with blood and mucus are features of anemia and diseases due to blood deficiency (pandu) caused by habitual consumption of clay [Cha.Sa.Chikitsa Sthana 16/30].
- The following table shows characteristic features of faecal matter in different types of fever (jwara) [Cha.Sa.Nidana Sthana 1/21-27], abdominal lumps(gulma) [Cha.Sa.Nidana Sthana 3/7-11] and diseases of digestion and metabolism (grahani) [Cha. Sa. Chikitsa Sthana 15/64, 66,70].
|Dosha dominance||Character of fecal matter in fever(jwara)/ abdominal lump(gulma)||Characteristic features of stool in diseases of digestion and metabolism (grahani) *|
|Vata dosha||Dark, blackish or reddish discoloration of stool and reduced tendency to evacuation of stool.||Painful defecation, takes more time for elimination, feces are watery, dry, small sized associated with flatus and undigested food. Frequency of defecation is increased.|
|Pitta dosha||Green or yellow coloration of stool.||The stools have undigested food particles with either bluish-yellowish tinge or yellow in color; loose/watery.|
|Kapha dosha||Whitish coloration of stool.||Stools are mixed with undigested items and mucous; heavy (sink in water).|
Feces as an assessment parameter in therapeutic procedures
Oleation therapy (snehana)
The character of stool is considered as an important parameter in assessment of the therapeutic oleation before therapeutic emesis (vamana) and purgation (virechana). The dietary fat consumption (in the form of ghee, oil, muscle fat and marrow) is increased for therapeutic purpose. The same is reflected in the consistency and fat content of stools.
a) Hard and dry feces are signs of inadequate oleation
b) Lubricated, soft and not well formed faeces indicate proper oleation.
c) Improperly formed and loose faeces indicate excess oleation. [Cha.Sa.Sutra Sthana 13/57-59]
Management of increased state
- Judicious application of cleansing therapies (shodhana) or medicines to facilitate the natural expulsion is indicated.[Su. Sa. Sutra Sthana 15/17]
- In case of diseases due to suppression of urge of defecation, fomentation, massage, sitz bath, per rectal suppositories, and therapeutic enema (basti) are prescribed. One should take food and drinks that facilitate bowel evacuation to remove obstruction. [Cha.Sa.Sutra Sthana 7/9]
Management of decreased state
- Therapies to stop the excessive elimination of feces (stambhana) is indicated.
- Consumption of substances having properties to increase bulk or promote formation of feces.[Su. Sa. Sutra Sthana 15/11]
Diet promoting the formation of feces (in case of scanty stool):
- Barley (yava) [Cha.Sa.Sutra Sthana25/40]
- A type of soup prepared of cereals and pulses (dhanya-yusha)made of barley(yava), green gram(mudga), black gram(masha), and shali type of rice, sesame seeds, Ziziphus jujuba Lamk (kola) and tender fruits of Aegle marmelos (bilva), sizzled with ghee and oil taken together with curd and the extract of pomegranate(dadima). One should take boiled shali rice along with this soup.
- Cream of curd sizzled with ghee and oil, and mixed with jaggery and ginger (shunthi)
- Sour fruits sizzled with ghee and oil.
- Meat soup
- The red variety of shali rice boiled by adding ghee and sour ingredients. [Cha.Sa.Chikitsa Sthana 19/35-41]
Role of tastes (rasa):
Excessive consumption of bitter taste (tikta rasa) food items leads to decrease of fecal matter. Excessive consumption of astringent food items (kashaya rasa) lead to constipation. [Cha.Sa.Sutra Sthana26/43]
- The faecal transplant, the transfer of faces or portions of the faecal matter from one organism into the gastrointestinal tract of another, is rapidly gaining attention as a treatment for human gut infections. Now a days, it is used as a general research tool for gain-of-function experiments in animal models.
- It is evident through some animal models that the gut micro biome has the functional capacity to induce or relieve metabolic syndrome. Faecal Microbiota Transplantation (FMT) is an emerging therapy with abundant potential in the field of management of obesity and metabolic syndrome.
- Recently, a research study has developed and validated a toilet paper–based fecal occult blood test for the use as a point-of-care test for the rapid (in 60 seconds) and easy testing of fecal occult blood which can be a promising tool for screening of colorectal cancer in public health domain.
Related theses works
1.Inya Lingu(2012): Study on Aetiopathogenesis of Vibandha in Geriatric persons and Role of Vaishvanara Churna in its Samprapti Vighatana, Department of Roganidana and Vikruti Vigyana, IPGT &RA, Jamnagar.
2.Ramanand Tiwari(2012) : Clinical Evaluation of Bilvadi Leha in the Management of Irritable Bowel Syndrome (IBS), Department of Roganidana and Vikruti Vigyana, IPGT &RA, Jamnagar.
- Available from http://namstp.ayush.gov.in/#/sat
- Jha Srujan. Amarkosha online application.
- Rose C, Parker A, Jefferson B, Cartmell E. The Characterization of Feces and Urine: A Review of the Literature to Inform Advanced Treatment Technology. Crit Rev Environ Sci Technol. 2015;45(17):1827-Vale
- Azzouz LL, Sharma S. Physiology, Large Intestine. [Updated 2020 Jul 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507857/
- Available from https://en.wikipedia.org/wiki/Human_feces cited on 24/12/2020
- Lacy BE, Patel NK. Rome Criteria and a Diagnostic Approach to Irritable Bowel Syndrome. J Clin Med. 2017;6(11):99. Published 2017 Oct 26. doi:10.3390/jcm6110099
- Arasaradnam RP, Brown S, Forbes A, et al. Guidelines for the investigation of chronic diarrhoea in adults: British Society of Gastroenterology, 3rd edition. Gut. 2018;67(8):1380-1399. doi:10.1136/gutjnl-2017-315909
- Available from https://en.wikipedia.org/wiki/Fecal_fat_test accessed on 29/12/2020
- Bojanova DP, Bordenstein SR. Fecal Transplants: What Is Being Transferred?. PLoS Biol. 2016;14(7):e1002503. Published 2016 Jul 12. doi:10.1371/journal.pbio.1002503.
- Zhang Z, Mocanu V, Cai C, et al. Impact of Fecal Microbiota Transplantation on Obesity and Metabolic Syndrome-A Systematic Review. Nutrients. 2019;11(10):2291. Published 2019 Sep 25. doi:10.3390/nu11102291
- Wang HY, Lin TW, Chiu SY, et al. Novel Toilet Paper-Based Point-Of-Care Test for the Rapid Detection of Fecal Occult Blood: Instrument Validation Study. J Med Internet Res. 2020;22(8):e20261. Published 2020 Aug 7. doi:10.2196/20261.