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Senna Laxative Use in Weight Control

Ji Eun Kim

November 18, 2009

Here are some Pictures from the websites that advertise the use of Senna.




The main purpose of using Senna is to treat constipation, which is a symptom where one gets dry stool and the evacuation is difficult and infrequent. Senna, which has many other names such as Cassia Angustifolia, helps this process by stimulating of intestinal peristalsis, flushing out the toxins from the body. The nature of Senna is to act as a laxative and to agitate the inner lining of the colon to execute the process. The mechanism of the herb, Senna comes from a shrub with yellow flowers, and there may be harmfulness of behavior caused by being overly dependent on this stimulant, and leading to diseases in colon, potassium deficiency and many others. Many consumerism diet sites are presenting this information, and these sites involve importing dry Senna leaves from India, China, and Arabic nations in order to sell their products. None are FDA approved, and may be seriously dangerous if not used with caution.


Senna Plant Description:

         Organic Senna is a small shrub, about 2 m in height. The stem is erect, smooth and pale green. The long spreading branches bears 5-8 jugate leaflets usually oval, lanceolate, glabrous. The leaves are thicker and stiffer, veins distinct on the under surface, brittle, grayish-green, of a faint, peculiar odor, and mucilaginous, sweetish taste. The flowers are small and yellow. (http://www.senna-leaves.com/)


How It Works:

         The medicinal action of Senna can be attributed mainly to “the anthraquinone glycosides, especially sennoside A and B. The breakdown of the anthraquinone glycosides in the digestive tract can occur in two ways. One; The glycosides are not absorbed in the upper gut but are converted by the microflora of the large intestine into active aglycones, principally rhein anthrone, which exert a laxative effect on the colon.” “Alternatively, in the presence of bile and the sugar, the free aglycone can be absorbed into the blood stream and secreted later into the colon. The final result is stimulation of the Auerbach plexus resulting in increased intestinal muscle contraction. In addition, its mucilage content decreases absorption of fluid leading to an enhancement of the final laxative action” (http://www.senna-leaves.com/).


The Indicators:

Its action being chiefly on the lower bowel, especially suitable in habitual costiveness. It increases the peristaltic movements of the colon by its local action upon the intestinal wall. It is a safe laxative used after surgical operations, after confinement, in the constipation of the feeble, and in many cases of inactive bowels, among infants and children (http://www.senna-leaves.com/).


History and Uses:

         Senna is also known by the names Alexandrian Senna and Rajavriksha. Cassia senna is native to tropical Africa, and is cultivated in Egypt and the Sudan; Cassia angustifolia is native to India, and is cultivated mainly in India and Pakistan.  The parts of this plant used medicinally are the leaves and the pods. The leaves have a purging quality, but afterwards may have a binding effect.  Both the leaves and pods are used in many over-the-counter pharmaceutical laxative preparations.  People in northern Africa and southwestern Asia have used Senna as a natural laxative for centuries.  It was considered a "cleansing" herb because of its cathartic effect.  In addition, the leaves were sometimes made into a paste, and applied to various skin diseases; acne and ringworm were both treated in this way (http://www.viable-herbal.com/singles/herbs/s530.htm).



Dangers & Risks

    Great care should be taken with the use of Senna.  Pregnant, nursing or menstruating women should not use Senna, and it is not appropriate for children under twelve years of age.  People with intestinal blockage, inflammatory bowel disease, intestinal ulcers, undiagnosed stomach pain or appendicitis symptoms must avoid Senna.  Senna can cause cramping, nausea and diarrhea, and the urine may take on a reddish hue (which is harmless).  Long-term use is not recommended (more than one week at a time), since it may cause dependence and a weakened colon, aggravate constipation and result in a loss of potassium and other vital minerals, which is particularly dangerous to people with heart rhythm irregularities.  Chronic constipation is usually indicative of another condition and should always be discussed with a physician.


Also, It can lead to reduced potassium levels in the body. Low potassium levels can result in muscle weakness and potentially dangerous changes in heart rhythm. It may also result in aching joints, weakened bones or muscles, loss of weight and decreased appetite. Cases of clubbing that occurs at the ends of the fingers have also been reported from taking Senna for long periods of time.


There are numerous side effects from its use including nausea, abdominal cramping, dizziness, and dehydration. Continued use causes more severe side effects including risk of heart attack and colon damage. Its laxative effect is probably the source of where weight loss is experienced due to the body fluids lost when Senna activates the colon. This usually consists of water and fecal matter; once food is digested, the weight is regained. This is the extent of the weight loss claims that are partially true — no other claims are backed by any sort of scientific evidence (http://www.diet-and-health.net/Naturopathy/Senna.html).


Numerous diet companies claim that Senna is a potent diet aid but they often do not explain how or why. Senna itself is recognized as a lethal stimulant laxative that stimulates the colon and causes it to contract and expel any substances inside of it which causes a laxative effect usually a couple of hours after it is absorbed. It is widely regarded as a natural laxative and is easily found in herbal stores (http://www.dietspotlight.com/senna-review/).







Here are some additional World Wide Web sites that you could use to gain more information on Senna:












































Review of Literature

Originally, Senna was identified as a way of releasing the bloating and constipation and known to be a safe drug tested by the physicians. Also, when used in proper conditions, it could help patients suffering from chronic constipation (Mascolo N, et.al, 1998). The Senna additives are known as stimulants, and drugs in this category stimulate intestinal motility and/or affect epithelial transport of water and electrolytes as anthranoids (Xing & Softer, 2001) and to irritate the interior and act as an aid to bowel movement. However, the continuation in use creates a cycle in which the colon is no longer able to function as properly due to the carcinogen feature of the herb. Although there have been some controversial views on using Senna laxative for dieting and weight loss, the common laxative, Senna, has been in use by the consumers to lose weight by purging, and this creates serious health risks for abusers.

In order to look at these serious purging cases of laxatives, one must look into the psychological perspective into the minds of these bulimic patients. For some, two motions daily may be normal whereas two motions weekly may be equally normal and satisfactory for another. Yet countless bowels are conditioned to ritual purgation on no other indication. Normal bowel action is dependent on there being sufficient food residue to initiate peristalsis, and constipation that follows the adoption. Some may just need more fiber and greens in their diets. The injudicious use of a purgative without good reason may start a vicious circle.

Normal defecation usually empties the sigmoid and descending colon, but the complete colonic evacuation after a purge is followed by a gap of two or three days during which sufficient residue accumulates to initiate a further defecation reflex. If, in the belief that he is still constipated, the patient takes a laxative again during this physiological lull, the stage is set for the development of what is, in fact, a form of drug-addiction (MacGregor 1960). Before discussing, therefore, the place of purgatives and laxatives in therapeutics, it is salutary to realize that the ill-effects of their abuse are far greater than the imagined ill-effects of constipation. Many of the bowel disturbances for which purgatives have been taken have not been indications for the prescription but have rather been the result of maladroit use of herbal laxative preparations (MacGregor 1960).

         When one decides to use this laxative in trying to lose weight, this psychological disorder is commonly known as Bulimia. Bulimia nervosa is a common eating disorder with three main models of purging. Resulting medical complications are related to the particular mode and frequency of purging. Commonly, there are oral and gastrointestinal complications along with serious electrolyte and endocrine complications. The majority of the medical complications of bulimia nervosa are treatable if diagnosed in a timely fashion. Some of these patients require inpatient hospitalization, and others can be managed along a continuum of outpatient care (Mehler et. Al., 2004).

         Patients with bulimia nervosa who purge through laxatives may also experience complaints referable to the colon. “Some patients may ingest up to 50 laxative pills per day to achieve their desired result. A review of 73 studies of laxative abuse revealed a lifetime incidence of 27.2%among patients with bulimia nervosa compared with 4.18% in the general population. Chronic abuse of stimulant cathartics, commonly containing senna or cascara, can cause melanosis coli – a reversible brown-black discoloration of the colonic mucosa and submucosa” (Mehler et. Al, 2004). In addition, these patients can develop an atonic colon, resulting in chronic constipation and laxative dependence, or a cathartic colon, a permanently flaccid and dilated colon that cannot circulate fecal material, resulting from damage to the neurological innervations of the intestine. Cathartic colon may cause refractory constipation requiring bowel resection. A previously abused stimulant laxative, phenolphthalein, was removed from the market a few years ago because of concern about its association with colon cancer (Mehler et. Al, 2004).

         Constipation is particularly problematic during attempts to withdraw stimulant laxatives in a bulimic patient. Laxative withdrawal is best managed by anticipatory counseling, “including setting the expectation that constipation and possibly rebound edema may occur but typically resolve within 10 days to 3 weeks” (Mehler et. Al, 2004). Patients should also be advised that regular exercise, adequate fluid intake, the addition of such bulk-forming agents as fiber or psyllium to the diet, and in some cases, an osmotic laxative, such as lactulose, will be necessary.

         Also, Patients’ misconceptions about stimulant laxatives should be addressed. Moreover, they should be told that laxatives are an ineffective means of weight loss because their site of action is the large intestine, where they cause temporary fluid loss without concomitant caloric losses. Relapse to stimulant laxative abuse will worsen the dependency on them and increase the risk of more refractory constipation. “Steatorrhea, protein-losing gastroenteropathy, and gastrointestinal bleeding have also been reported as a result of laxative abuse” (Mehler et. Al, 2004).        

         Also, we most note that in modern drug therapy the use of natural drugs should only be justified if the chemical, pharmacological and toxicological characteristics of the drugs are accurately defined. Commercial senna preparations do not fulfil this requirement and packages usually only indicate the amount of sennosides present in the product, although considerable amounts ranging from 2% to 95%, as stated by the manufacturer of chemically unidentified components are also contained which originate from the plant or are formed during extraction. These impurities may be synergistic with or antagonistic to the drug substance or may be responsible for side effects caused by the product. A case in point is Senna products, the impurities of which may be causing many of the reported side effects (Hietela et al., 1987).

         Senna is one of the well-known anthranoid-containing herbal drugs used as laxatives Although the stimulant laxatives including senna have been recommended for short-term treatment of acute constipation many people use them for long periods without medical supervision. The concerns about possible health problems resulting from chronic abuse of anthranoid laxatives prompted a number of studies aimed at investigating their genotoxic and potential carcinogenic effects. Some studies indicated that anthranoids could be carcinogenic in rodents. Although epidemiologic studies on cancer risk assessment in humans for exposure to anthranoids failed to confirm the carcinogenicity of these drugs so far, they are still considered as potential carcinogens based on the results of in vitro toxicity and in vivo animal tests (Al-Dakan et.Al, 1995). Thus, the possibility of Cancer forming agents are within the use of Senna, and this risk should not be worth taking for the loose stools that it provides in illusion of weight loss.

         One study with survey data that were gathered from 39 consecutive patients diagnosed with bulimia nervosa that were seeking treatment. A survey of area outlets was conducted to establish a database of available agents. Putative active ingredients were identified. As a result, Alternative medicines are frequently used in the population of patients seeking treatment for bulimia nervosa. An abundance of products are available with potentially significant toxicities (Roerig 2002).  Studies have shown that bulimic patients may consume a wide range of herbal or alternative remedies ( for example for their stimulant or diuretic properties) which may have coetaneous side-effects. The clinician should specifically enquire about the use of herbal products as most patients do not consider such remedies to be drugs and may not see the need to reveal their use. (Gupta & Gupta 2002).

         On a lighter note, one study was done in order to investigate the efficacy and cost effectiveness of an herbal tea containing Senna, Smooth Move, in nursing home residents with chronic constipation. The subjects consisted of 483-bed nursing home in Allentown, Pennsylvania, operated by Lehigh County Government and a total of 86 nursing home residents with chronic constipation. The primary efficacy parameter was the difference in total number of bowel movements. As a result, in comparison to placebo, in the intention to treat (ITT analysis) there was a statistically significant increase in the number of bowel movements in the Smooth Move group. The Smooth Move group compared with the placebo group experienced an average of 4.14 more bowel movements during the 28-day study period versus the 28-day pre-study period. In their conclusion, the Smooth Move herbal tea, when added to the standard treatment regimen for nursing home residents with chronic constipation, increased the average number of bowel movements compared to the addition of a placebo tea (Bub et. Al 2005). This study clearly shows the effectiveness of the herb in helping patients with chronic constipation patients. However, this must be monitored in order for the safety of all users.

         In the end, there will be continued bulimic patients who are willing to believe that this use of Senna laxative will give them the results they wish. However, as studies have shown, it is dangerous for any one to overdose on any form of consumer friendly products that advertise fast weight loss, and when taking any form of herbal or medication not approved by the FDA, one should be much attentive to details and research.






Al-Dakad AA, Mohammed Al-Tuffail M, and Hannan MA. (1995) Cassia Senna Inhibits Mutagenic Activities of Benzo[a]- pyrene, Aflatoxin B1, Shamma and Methyl Methanesaonate. Pharmacology & Toxicology  77, 288-292


Bub S, Brinckmann J, Cicconetti G, and Valentine B (2006) Efficacy of an Herbal Dietary Supplement (Smooth Move) in the Management of Constipation in Nursing Home Residents: A Randomized, Double-Blind, Placebo-Controlled Study. JAMDA. 556-61.


Gupta MA and Gupta AK. (2002) Dermatological Complications. European Eating Disorders Review.  1(8), 134-143.


Hietala P, Marvola M, Parviainen T, and Lainonen H. (1987) Laxative Potency and Acute Toxicity of Some Anthraquinone Derivatives, Senna Extracts and Fractions of Senna Extracts. Pharmacology & Toxicology 61, 153-156.


MacGregor AG, (1960). Drug Treatment of Disease :Purgatives and Laxatives. British Medical Journal. 1422-1424.


Mascolo N, Capasso R, and Capasso F. (1998). Senna: A Safe and Effective Drug.

Phytotherapy Research.  12(S), 143–145.


Mehler PS,  Crews C, and Weiner K. (2004). Bulimia: Medical Complications. Journal of Women’s Health. 13(6), 668-675.



Roerig JL,  Mitchell JE,  Zwaan M, Wonderlich SA, Kamran S, Engbloom S, Burgard M,

and Lancaster K. (2002).  The Eating Disorders Medicine Cabinet Revisited: A Clinician’s Guide to Appetite Suppressants and Diuretics. Wiley Periodicals, Inc.



Xing JH, Softer EE. (2001). Adverse Effects of Laxatives the Department of Gastroenterology. Dis Colon Rectum, 44(8), 1202-1209.





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