Rhubarb

Share
Print
Share
Print
Rhubarb

Common Names

  • Turkish rhubarb
  • Chinese rhubarb
  • Tai huang
  • Da huang

For Patients & Caregivers

How It Works

Rhubarb acts as a stimulant laxative, but has not been shown to treat or prevent cancer.

Rhubarb is a perennial herb, and the stalks are sometimes consumed as food. In Traditional Chinese Medicine (TCM), the rhizome and roots are used as laxatives and to treat ulcers, constipation, diarrhea, high blood pressure, and cancer. In lab animals, compounds in rhubarb called anthraquinones reduced pain, inflammation, and some tumors.

Studies in humans are limited, but suggest rhubarb can improve feeding tolerance and relieve gastrointestinal dysfunction in very ill patients. It may also reduce excess blood levels of pancreatic enzymes and pancreatitis events caused by some procedures. Other initial studies suggest it can treat mouth sores or help reduce radiation side effects. Additional studies are needed to determine safety and effectiveness.

Rhubarb is considered to be a stimulant laxative. It is also a component of Essiac tea. Patients and physicians should be aware of the potential for additive effects.

Purported Uses
  • To reduce cancer treatment side effects One study suggests that a rhubarb extract may reduce side effects from radiation therapy in lung cancer patients. Additional studies are needed.
  • To relieve constipation Rhubarb acts as a laxative, although clinical trials have not tested this use.
  • As a fever reducer There is no scientific evidence to support this claim.
  • To suppress the immune system Laboratory data shows that rhubarb decreases the activity of isolated immune cells.
  • To reduce inflammation Some studies suggest that rhubarb has anti-inflammatory effects.
  • To treat infections There is no scientific evidence to support this claim.
  • To treat ulcers A small study suggests rhubarb may be useful for treating oral ulcers. More studies are needed.
Do Not Take If
  • You are taking digoxin: Potassium loss due to the laxative effect of rhubarb means it may increase the risk of low potassium levels.
  • You are taking cytochrome P450 substrate drugs: Rhubarb may reduce the effectiveness of these drugs, but clinical significance has yet to be determined.
  • You are taking melatonin: Lab studies suggest that using both products together may affect the way melatonin is metabolized, but clinical relevance is not yet known.
  • You are taking cyclosporine: In lab studies, rhubarb decreased cyclosporine bioavailablity. Clinical relevance is not yet known.
  • You are taking methotrexate: In lab studies, rhubarb increased exposure to methotrexate. However, clinical relevance is not clear.
  • You have kidney disease: Rhubarb is high in oxalates and may cause kidney problems in some individuals.
Side Effects

Case report

  • Kidney damage/failure: In a type-1 diabetic patient with normal kidney function following excess ingestion of rhubarb and in a 75-year-old man from excess intakes of rhubarb stew over a few weeks.
  • Dark pigment deposits in the colon: In a 67-year-old woman with long-term use of a natural fiber supplement containing rhubarb. This condition is often associated with chronic laxative use. It was reversed after a long period of product discontinuation and repeat colonoscopy.
Special Point
  • Rhubarb is high in oxalates, and may cause kidney problems in some individuals.
Back to top

For Healthcare Professionals

Scientific Name
Rheum palmatum, Rheum officinale
Clinical Summary

Rhubarb, a perennial herb, is cultivated in many parts of the world. The stalks are consumed as food, and the rhizome and root are widely used in Traditional Chinese Medicine for a variety of conditions including cancer, constipation, diarrhea, gastrointestinal ulcers, and hypertension (1) (3). The anthraquinones and tannins in rhubarb are thought responsible for its laxative and constipating effects, respectively (4).

In preclinical studies, rhubarb demonstrated anticancer (20), antimetastatic (21), radioprotective (22), and estrogen-receptor-modulating (13) effects. The constitutent aloe-emodin has demonstrated anticancer (5) (6) (27) and anti-leishmanial (30) effects. It was also shown to enhance the effects of sorefenib (28) and cisplatin (29).

Evidence for safety and efficacy in humans is limited. Preliminary studies suggest rhubarb may have added benefits for patients with sepsis when used with the protease inhibitor ulinastatin (34), or help treat recurrent aphthous stomatitis (25). Other data suggest it may improve feeding tolerance and relieve gastrointestinal dysfunction in critically ill patients (23) or help prevent procedure-related pancreatitis and hyperamylasemia in high-risk patients (24). A meta-analysis suggests that rhubarb adjuvant to early enteral nutrition may benefit patients with severe acute pancreatitis (35), but a systematic review does not support its use for gastrointestinal failure in ICU patients (36). In a small study of lung cancer patients, a rhubarb extract reduced radiation-induced lung toxicity and increased pulmonary function (7).

Rhubarb is considered to be a stimulant laxative and is high in oxalates (37). It is also a component of Essiac tea. Patients and physicians should be aware of the potential for additive effects.

Purported Uses
  • Cancer
  • Constipation
  • Fever
  • Immune suppression
  • Inflammation
  • Microbial infection
  • Ulcers
Mechanism of Action

When used in small doses, the tannin content in rhubarb has a constipating effect. At higher doses, however, the hydrolyzed metabolites of emodin and sennidin stimulate the gastrointestinal tract and produce a laxative effect (4). The actions of anthraquinones on rheinanthrone, which is transformed from sennoside A, may promote the purgative effects of sennoside A (16).

The anti-inflammatory activity of emodin may mediate rhubarb’s hepatoprotective effects in rats with cholestatic hepatitis (11). Lindeyin, a phenolic gallylglucoside, exhibits analgesic and anti-inflammatory properties in animal models. Catechin, epicatechin, procyanidins, and gallylglucose were also shown to inhibit hyaluronidase (10) (12).

Additional studies show that aloe-emodin exerts anti-proliferative activity, inducing cell cycle arrest in cancer cell lines (6). Anthraquinone extracts of rhubarb were shown to induce cytotoxicity in cancer cell lines (5) and tumor (sarcoma 37, mammary, and Ehrlich) necrosis in mice (1), although this has not been demonstrated in humans. Another study showed that emodin inhibits human cancer cell invasiveness by specifically antagonizing the adenosine 5’-triphosphate (ATP)-gated Ca(2+)-permeable channel P2X7 receptor (P2X7R) (17).

Adverse Reactions

Case reports

  • Kidney failure: In a type-1 diabetic patient with normal kidney function following excess ingestion of rhubarb (18), and in a 75-year-old man from excessive intakes of rhubarb stew over a few weeks (37). Rhubarb is high in oxalates.
  • Melanosis coli: In a 67-year-old woman with long-term use of a natural fiber supplement containing rhubarb. This condition is often associated with chronic laxative use and causes dark cellular pigment deposits in the colon. It was reversed after product discontinuation and upon repeat colonoscopy 1.5 years later (38).
Herb-Drug Interactions
  • Digoxin: Potassium loss due to rhubarb’s laxative effect can increase the risk of hypokalemia. (9)
  • Cytochrome P450 substrates: In animal models, rhubarb induces CYP3A and CYP2D6 (15) (19), while the compound rhein inhibits CYP2E1, CYP3A, and CYP2C9, and to a lesser extent CYP1A2 and CYP2D6 (39). Clinical relevance is not known.
  • Melatonin: A study using human primary hepatocytes showed that concomitant use can cause metabolic disorder of melatonin (31). Clinical relevance is not known.
  • Cyclosporine: Rhubarb decreased the bioavailablity of cyclosporine in a murine model. Clinical relevance is not known (32).
  • Methotrexate: Rhubarb was shown to increase exposure to methotrexate in a murine model. Clinical relevance is not clear (33).
Dosage (OneMSK Only)
References
  1. Mantani N, et al. Rhubarb use in patients treated with Kampo medicine—a risk for gastric cancer? Yakugaku Zasshi 2002;122:403-5.
  2. Huang KC. The Pharmacology of Chinese Herbs, 2nd ed. New York: CRC Press; 1999.
  3. Zhang ZJ, Cheng WW, Yang YM. Study on low-dose of processed rhubarb in preventing pregnancy induced hypertension. Chung-Hua Fu Chan Ko Tsa Chih [Chinese Journal of Obstetrics & Gynecology] 1994;29:463-4, 509.
  4. Peigen X, Liyi H, Liwei W. Ethnopharmacologic study of chinese rhubarb. J Ethnopharmacol 1984;10:275-93.
  5. Cui XR, Tsukada M, Suzuki N, et al. Comparison of the cytotoxic activities of naturally occurring hydroxyanthraquinones and hydroxynaphthoquinones. Eur J Med Chem. Jun 2008;43(6):1206-1215.
  6. Guo JM, Xiao BX, Liu Q, Zhang S, Liu DH, Gong ZH. Anticancer effect of aloe-emodin on cervical cancer cells involves G2/M arrest and induction of differentiation.Acta Pharmacol Sin. Dec 2007;28(12):1991-1995.
  7. Yu HM, Liu YF, Cheng YF, Hu LK, Hou M. Effects of rhubarb extract on radiation induced lung toxicity via decreasing transforming growth factor-beta-1 and interleukin-6 in lung cancer patients treated with radiotherapy. Lung Cancer. Feb 2008;59(2):219-226.
  8. Newall CA, et al. Herbal Medicines: A Guide for Health-Care Professionals. London: Pharmaceutical Press; 1996.
  9. Brinker F. Herb Contraindications and Drug Interactions, 3rd ed. Sandy (OR): Eclectic Medical Publishing; 2001.
  10. Tamayo C, et al. The chemistry and biological activity of herbs use in Flor-essence herbal tonic and Essiac. Phytother Res 2000;14:1-14.
  11. Ding Y, Zhao L, Mei H, et al. Exploration of Emodin to treat alpha-naphthylisothiocyanate-induced cholestatic hepatitis via anti-inflammatory pathway. Eur J Pharmacol. Aug 20 2008;590(1-3):377-386.
  12. Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine, Expanded Commission E Monographs. Austin: American Botanical Council; 2000.
  13. Kang SC, Lee CM, Choung ES, et al. Anti-proliferative effects of estrogen receptor-modulating compounds isolated from Rheum palmatum. Arch Pharm Res. 2008 Jun;31(6):722-6.
  14. Li WY, Chan SW, Guo DJ, et al. Water extract of Rheum officinale Baill. induces apoptosis in human lung adenocarcinoma A549 and human breast cancer MCF-7 cell lines. J Ethnopharmacol. 2009 Jul 15;124(2):251-6.
  15. Tang JC, Zhang JN, Wu YT, Li ZX. Effect of the water extract and ethanol extract from traditional Chinese medicines Angelica sinensis (Oliv.) Diels, Ligusticum chuanxiong Hort. and Rheum palmatum L. on rat liver cytochrome P450 activity. Phytother Res. 2006 Dec;20(12):1046-51.
  16. Takayama K, Tsutsumi H, Ishizu T, Okamura N. The influence of rhein 8-O-β-D-glucopyranoside on the purgative action of sennoside A from rhubarb in mice.Biol Pharm Bull. 2012;35(12):2204-8.
  17. Jelassi B, Anchelin M, Chamouton J, et al. Anthraquinone emodin inhibits human cancer cell invasiveness by antagonizing P2X7 receptors.Carcinogenesis. 2013 Jul;34(7):1487-96.
  18. Albersmeyer M, Hilge R, Schröttle A, et al. Acute kidney injury after ingestion of rhubarb: secondary oxalate nephropathy in a patient with type 1 diabetes. BMC Nephrol. 2012 Oct 30;13:141.
  19. Gao J, Shi Z, Zhu S, et al. Influences of processed rhubarbs on the activities of four CYP isozymes and the metabolism of saxagliptin in rats based on probe cocktail and pharmacokinetics approaches.J Ethnopharmacol. 2013 Jan 30;145(2):566-72.
  20. El-Saied MA, Sobeh M, Abdo W, et al. Rheum palmatum root extract inhibits hepatocellular carcinoma in rats treated with diethylnitrosamine. J Pharm Pharmacol. 2018 Jun;70(6):821-829.
  21. Chen YY, Hsieh MJ, Hsieh YS, et al. Antimetastatic effects of Rheum palmatum L. extract on oral cancer cells. Environ Toxicol. 2017 Oct;32(10):2287-2294.
  22. Lu K, Zhang C, Wu W, Zhou M, Tang Y, Peng Y. Rhubarb extract has a protective role against radiation-induced brain injury and neuronal cell apoptosis. Mol Med Rep. 2015 Aug;12(2):2689-94.
  23. Zhang X, Wang L, Chen DC. Effect of Rhubarb on Gastrointestinal Dysfunction in Critically Ill Patients: A Retrospective Study Based on Propensity Score Matching. Chin Med J (Engl). 2018 May 20;131(10):1142-1150.
  24. Wang C, Li Q, Ye P, et al. Value of Raw Rhubarb Solution in the Precaution of Post-endoscopic Retrograde Cholangiopancreatography Pancreatitis in Patients with High-Risk Factors: A Predictive Random Compared Research in One Center. Dig Dis Sci. 2017 Apr;62(4):1043-1050.
  25. Rodríguez-Archilla A, Raissouni T. Randomized clinical trial of the effectiveness of complementary therapies for recurrent aphthous stomatitis. Med Clin (Barc). 2017 Jul 21;149(2):55-60.
  26. Wang L, Pan S. Adjuvant treatment with crude rhubarb for patients with acute organophosphorus pesticide poisoning: A meta-analysis of randomized controlled trials. Complement Ther Med. 2015 Dec;23(6):794-801.
  27. Chen Y, Li J, Hu J, et al. Emodin enhances ATRA-induced differentiation and induces apoptosis in acute myeloid leukemia cells. Int J Oncol. 2014 Nov;45(5):2076-84.
  28. Kim YS, Lee YM, Oh TI, et al. Emodin Sensitizes Hepatocellular Carcinoma Cells to the Anti-Cancer Effect of Sorafenib through Suppression of Cholesterol Metabolism. Int J Mol Sci. 2018 Oct 12;19(10).
  29. Li X, Wang H, Wang J, et al. Emodin enhances cisplatin-induced cytotoxicity in human bladder cancer cells through ROS elevation and MRP1 downregulation. BMC Cancer. 2016 Aug 2;16:578.
  30. Dalimi A, Delavari M, Ghaffarifar F, Sadraei J. In vitro and in vivo antileishmanial effects of aloe-emodin on Leishmania major. J Tradit Complement Med. 2015 Jan 31;5(2):96-9.
  31. Jiang W, Tian X, Wang Y, et al. The natural anthraquinones from Rheum palmatum induced the metabolic disorder of melatonin by inhibiting human CYP and SULT enzymes. Toxicol Lett. 2016 Nov 16;262:27-38.
  32. Yu CP, Lin HJ, Lin SP, et al. Rhubarb decreased the systemic exposure of cyclosporine, a probe substrate of P-glycoprotein and CYP 3A. Xenobiotica. 2016 Aug;46(8):677-82.
  33. Shia CS, Juang SH, Tsai SY, Lee Chao PD, Hou YC. Interaction of rhubarb and methotrexate in rats: in vivo and ex vivo approaches. Am J Chin Med. 2013;41(6):1427-38.
  34. Meng F, Du C, Zhang Y, et al. Protective effect of rhubarb combined with ulinastatin for patients with sepsis. Medicine (Baltimore). Feb 2020;99(7):e18895.
  35. Chen X, Yang K, Jing G, et al. Meta-Analysis of Efficacy of Rhubarb Combined With Early Enteral Nutrition for the Treatment of Severe Acute Pancreatitis. JPEN J Parenter Enteral Nutr. Mar 18 2020.
  36. Jin W, Guo X, Li Q, et al. Potential preventive and therapeutic effect of Chinese herb rhubarb (da huang) for intensive care unit/pediatric intensive care unit gastrointestinal failure patients: A protocol for systematic review. Medicine (Baltimore). May 2020;99(20):e20188.
  37. Gliese KM, Løth N, Hornum M. [Acute haemodyalysis-requiring kidney failure due to massive intake of rhubarb stew]. Ugeskr Laeger. May 18 2020;182(21).
  38. Klair JS, Chandra S, Johlin FC. Melanosis Coli due to Rhubarb Supplementation. ACG Case Rep J. May 2019;6(5):e00092.
  39. Tang JC, Yang H, Song XY, et al. Inhibition of cytochrome P450 enzymes by rhein in rat liver microsomes. Phytother Res. Feb 2009;23(2):159-164.
Back to top
Back to top
Email your questions and comments to aboutherbs@mskcc.org.

Last Updated