Senna (Cassia senna)
Natural Standard Bottom Line Monograph, Copyright © 2013 (www.naturalstandard.com). Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.
While some complementary and alternative techniques have been studied scientifically, high-quality data regarding safety, effectiveness, and mechanism of action are limited or controversial for most therapies. Whenever possible, it is recommended that practitioners be licensed by a recognized professional organization that adheres to clearly published standards. In addition, before starting a new technique or engaging a practitioner, it is recommended that patients speak with their primary healthcare provider(s). Potential benefits, risks (including financial costs), and alternatives should be carefully considered. The below monograph is designed to provide historical background and an overview of clinically-oriented research, and neither advocates for or against the use of a particular therapy.
Aden senna, Agiocur®, Agiolax®, Alexandrian senna, Alexandrinische Senna (German), barakol, casse, Cassia acutifolia, Cassia alata, Cassia angustifolia, Cassia marilandica, Cassia obtusifolia L., Cassia senna, Cassia tora L., Cassiae senna, cassine, dianthrones, extractum Sennae, Fletcher's Castoria®, Glysennid®, hairy roots, Indian senna, Khartoum senna, locust plant, Lunelax®, Mecca senna, Nubian senna, Perdiem, Prunasine®, Pursennid®, rhein, rhein 8-O-glucoside, rheinanthrone, sena alejandrina (Spanish), séné d'Egypte (French), Senna alata (L.) Roxb. (Fabaceae), Senna alexandrina spp., Senna didymobotrya (Fresen.) H.S.Irwin & Barneby, senna fruit, Senna obtusifolia (L.), Senna occidentalis (L.) Link (Fabaceae), senna pods, Senna racemosa, Senna spectabilis, Senna tora (L.) Roxb., Sennae folium, Sennae fructus, Sennatin®, sennidine monoglycosides, sennoside A, sennoside B, Senokot®, Sofsena™, Tinnevelly senna fruits, true senna, winged senna, X-prep®.
The leaves or pods of the senna plant (Cassia senna) have been used by Arab physicians for their laxative properties since at least the ninth Century. Today, senna is a U.S. Food and Drug Administration (FDA)-approved nonprescription drug and an ingredient in several commercial laxatives.
There are over 400 known species of Cassia. Both the leaves and the seedpods (fruit) have laxative activity, due to the presence of compounds called anthraquinones. These compounds found in senna are also found in other plants with laxative properties, including cascara (Cascara sagrada), rhubarb (Rheum spp.), and aloe (Aloe vera). Senna accelerates defecation, in contrast to softening the stools, as some laxatives do. When taken at much higher than recommended doses or when used for the long term (laxative abuse), adverse effects, such as low blood potassium, may occur.
Some evidence supports the use of senna in adults for the treatment of chronic constipation or constipation induced by childbirth or drugs. In children, the available evidence suggests that mineral oil and lactulose may be safer and more effective than senna for treating chronic constipation. Some experts believe that senna is a more acceptable laxative than cascara or aloe for drug-induced constipation. Approximately 80% of terminal cancer patients who are taking opioids for pain relief require laxatives. Some evidence suggests that senna may be as effective and safe as lactulose for these patients.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
The available evidence suggests that mineral oil and lactulose may be safer and more effective laxatives than senna for treating children with chronic constipation. Further research is required before conclusions may be made.
Although senna is commonly used to reduce constipation, the available clinical research is mixed. Some studies have shown that senna may be more effective than some other laxatives and have fewer side effects. Further trials are needed before a conclusion may be made.
Some evidence supports the use of senna as an adjunct therapy in the treatment of cancer patients who have constipation as a result of taking opioids for pain. Further research should assess the length of time such patients may safely use senna.
Senna has been examined as a potential treatment for postoperative constipation. Additional research is needed before a conclusion may be made.
Diagnostic procedure (abdominal area)
Senna has been examined as a method for preparing the bowel before diagnostic procedures that require clear visualization of the abdominal area. Further studies are needed in this area.
Laxative/bowel preparation for procedures (colonoscopy)
Data on the use of senna for cleaning the colon in preparation for colonoscopy are mixed. Some adverse effects have been reported with this use. Additional research is needed before a conclusion can be made.
*Key to grades:A: Strong scientific evidence for this use; B: Good scientific evidence for this use; C: Unclear scientific evidence for this use; D: Fair scientific evidence against this use (it may not work); F: Strong scientific evidence against this use (it likely does not work).
The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious and should be evaluated by a qualified health care professional.
Anal fissures (children, adjunct), antibacterial, back pain, breast cancer, cleansing, gastrointestinal disorders, hemorrhoids, insecticidal, mosquito repellant, skin conditions (topical), snakebites, weight loss.
The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (18 years and older)
Doses must be determined for each patient, due to individual variability. A tea may be made from dried senna leaves or fruits.
For chronic constipation, 1-2 tablets (or one teaspoon) of Senokot® have been taken daily by mouth. One to two tablets of Senokot-S®, increasing to a maximum of three tablets twice daily, or reducing to one tablet daily or every other day, have been taken by mouth in a nursing home setting. A dose of 14.8 grams of Agiolax® (senna combined with a bulk laxative) has been taken by mouth daily in geriatric patients. Four tablets daily of Senokot®, given in divided doses in the morning and evening until a bowel movement occurs, or a maximum of 16 doses, have been taken by mouth for postpartum constipation. One teaspoon of senna granules, consisting of 450 milligrams of Cassia acutifolia pod, has been taken by mouth once daily after childbirth, followed by either one-half or one whole teaspoon of senna granules at bedtime. One teaspoon of water-soluble senna extract, standardized to 20 milligrams of sennosides, has been added to one cup of water and taken by mouth daily for at least six weeks. Glysennid® has been taken by mouth in an initial dose of one tablet nightly, increased (to a maximum of three tablets daily) or decreased (to a minimum of one tablet daily) according to individual response. Senna leaves or pods have been taken by mouth in doses of 0.6-2 grams daily, together with a dose of 20-30 milligrams of sennoside B.
For constipation (opioid-induced), half of a Senokot® concentrated senna tablet has been taken by mouth to counteract each 60 milligrams of codeine or its equivalent. Senna (starting with 0.4 milliliters daily) has been taken by mouth for 27 days.
For constipation (postoperative), 1-2 tablets (one teaspoon) of senna (Senokot®) has been taken by mouth as a single dose.
For a laxative or bowel preparation for procedures, senna (one package diluted in a glass of water) has been taken by mouth the evening before surgery. Two tablets of Senokot® DX (14 milligrams of sennosides A and B) have been taken by mouth on the two evenings before X-ray examination. A dose of one milliliter per kilogram of body weight (to a maximum of 75 milliliters) of a syrup containing 2.0 milligrams of sennoside A and B per milliliter (X-prep®) has been taken by mouth. A dose of one milliliter per kilogram of body weight of Prunasine® (to a maximum dose of 75 milliliters) has been taken by mouth. A dose of 180 milligrams of senna has been taken by mouth one day prior to colonoscopy. A dose of 75 milliliters of a senna laxative has also been taken by mouth the day before colonoscopy. Twenty-four tablets of 12 milligrams senna have been divided into two doses and taken by mouth.
Children (under 18 years old)
There is no proven safe or effective dose for senna in children.
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Avoid with known allergy or hypersensitivity to senna, its constituents, or members of the Fabaceae family. Occupational exposure to senna may cause allergy in the absence of increased risk of asthma.
Side Effects and Warnings
Senna is likely safe for short-term use for constipation, including by the elderly, women after childbirth, and cancer patients taking narcotic drugs. The adverse effects of senna reported in clinical trials are mostly gastrointestinal in nature. Experts have suggested that the benefits of senna during pregnancy be weighed against possible adverse effects.
Senna may cause abdominal cramps and pain; aching joints; acquired common variable hypogammaglobulinemia with absence of circulating B lymphocytes; bloating; cachexia (wasting); cardiac arrest; changes in colon anatomy or damage to the colon wall; chronic liver damage; constipation; decrease in heart rate; dependence on senna; diaper rash; diarrhea; finger clubbing; flatulence; hallucinations; hepatitis; hypertrophic osteoarthropathy; incontinence; increased calcium levels in the kidney; intestinal nerve damage; low blood potassium; low blood pressure; muscle weakness; nausea; portal vein thrombosis; reduced absorption of some drugs; respiratory failure; tetany; urine with reddish, pink, or brownish color; urothelial cancer; vomiting; weakened bones; or weight loss.
Chronic laxative abuse may appear with watery diarrhea, abdominal discomfort (sometimes pain), muscle weakness, lassitude with low blood potassium, melanosis coli (symptom-free pigmentation of the colon, observed at colonoscopy), and the barium enema appearance of a "cathartic colon." Low levels of potassium in the blood may impair insulin secretion.
Although the effect has not been well studied in humans, senna may decrease the absorption of some herbs and supplements, due to the presence of anthranoid compounds.
Senna may increase the risk of bleeding. Caution is advised in patients with bleeding disorders or those taking drugs, herbs, or supplements that may increase the risk of bleeding. Dosing adjustments may be necessary.
Use cautiously in patients who have had an obstruction of the gastrointestinal tract.
Use cautiously in patients with hemorrhoids, stomach ulcers, or inflammatory bowel condition, as senna may cause these conditions to worsen.
Use cautiously in patients taking diuretics or other laxatives, as senna may further reduce levels of blood potassium.
Use cautiously in patients taking digoxin, as senna may increase side effects of digoxin.
Use cautiously in patients with a history of gallstones, as senna may quicken passage through the gastrointestinal tract, which may increase the risk of gallstones.
Use cautiously in children less than 12 years of age.
Avoid long-term use of senna (e.g., more than 7-10 days), due to the potential for side effects, including potentially dangerous changes in heart rhythm. Long-term use of laxatives may lead to "lazy-bowel syndrome," in which the stomach and intestines gradually lose the ability to contract without being stimulated by the laxative.
Avoid in patients with known allergy or hypersensitivity to senna, its constituents, or members of the Fabaceae family.
Pregnancy and Breastfeeding
Use of senna by pregnant or breastfeeding women remains controversial. The American Academy of Pediatrics has classified senna as "usually compatible with breastfeeding." The World Health Organization regards its use while breastfeeding as safe for the infant. However, senna use is contraindicated in Britain and Germany. Clinical trials have reported that senna is safe and effective for women experiencing postpartum-induced constipation, with a lack of adverse effects on breastfed babies. One study reported that senna does not appear to be secreted in breast milk. Experts have suggested that the benefits of senna during pregnancy be weighed against possible adverse effects.
Constipation is a common complaint during pregnancy. The use of fiber supplements and senna has been supported.
Older senna products may have caused increased frequency of diarrhea in breastfed infants, but studies of modern products found this effect lacking.
Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.
Interactions with Drugs
Although the effect has not been well studied in humans, senna may decrease the absorption of some drugs, due to the presence of anthranoid compounds.
Senna may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin®) or heparin, antiplatelet drugs such as clopidogrel (Plavix®), and nonsteroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).
Senna may also interact with antibiotics, anticancer agents, antivenom agents, antiviral agents, digoxin, diuretics, hormonal agents, or laxatives.
Interactions with Herbs and Dietary Supplements
Although the effect has not been well studied in humans, senna may decrease the absorption of some herbs and supplements, due to the presence of anthranoid compounds.
Senna may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.
Senna may also interact with aloe, antibacterials, anticancer agents, antioxidants, antivenom agents, antivirals, digoxin, diuretics, hormonal herbs and supplements, laxatives, Rhamnus cathartica, Rhamnus frangula, Rhamnus purshiana, or yellow dock.
This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.
Fingerhut A, Hay JM. Single-dose ceftriaxone, ornidazole, and povidone-iodine enema in elective left colectomy. A randomized multicenter controlled trial. The French Association for Surgical Research Arch Surg 1993;128(2):228-232. View Abstract
Fournier AM. [Use of senna for the acceleration of small intestine transit in hospital radiology]. Mars Med 1971;108(6):469-474. View Abstract
Glatzel, H. [Senna--an old drug in a new form]. Z Allgemeinmed 1970;46(2):82-84. View Abstract
Godding EW. Laxatives and the special role of senna. Pharmacology 1988;36 Suppl 1:230-236. View Abstract
Han RX. [Study of the cleansing effect of senna on the intestinal tract]. Zhonghua Hu Li Za Zhi 1989;24(5):273-275. View Abstract
Heaton KW, Cripps HA. Straining at stool and laxative taking in an English population. Dig Dis Sci 1993;38(6):1004-1008. View Abstract
Langmead L, Rampton DS. Review article: herbal treatment in gastrointestinal and liver disease--benefits and dangers. Aliment Pharmacol Ther 2001;15(9):1239-1252. View Abstract
Mishalany H. Seven years' experience with idiopathic unremitting chronic constipation. J Pediatr Surg 1989;24(4):360-362. View Abstract
Monias MB. Standardized senna concentrate in postpartum bowel rehabilitation. Md State Med J 1966;15(2):32-33. View Abstract
No authors listed. Senna and habituation. Pharmacology 1992;44 Suppl 1:30-32. View Abstract
Pahor M, Mugelli A, Guralnik JM, et al. Age and laxative use in hospitalized patients. A report of the "Gruppo Italiano di Farmacovigilanza nell'Anziano--GIFA". Aging (Milano) 1995;7(2):128-135. View Abstract
Senna in the puerperium. Pharmacology 1992;44 Suppl 1:23-25. View Abstract
Tooson JD, Gates LK, Jr. Bowel preparation before colonoscopy. Choosing the best lavage regimen. Postgrad Med 1996;100(2):203-12, 214. View Abstract
Vaidyanathan S, Soni BM. Bluish discolouration of urine drainage tube and bag in a female patient with spina bifida, paraplegia, and suprapubic cystostomy. ScientificWorldJournal 2007;7:1070-1072. View Abstract
Valverde A, Msika S, Kianmanesh R, et al. Povidone-iodine vs sodium hypochlorite enema for mechanical preparation before elective open colonic or rectal resection with primary anastomosis: a multicenter randomized controlled trial. Arch Surg 2006;141(12):1168-1174. View Abstract
Copyright © 2013 Natural Standard (www.naturalstandard.com)
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.
March 22, 2017