Traditional Chinese medicine has used rhubarb for thousands of years, as a remedy for gut disorders, liver and kidney disease, poisoning, and more. Modern research has backed up most of these uses but also emphasized important limitations and safety concerns. Read on to learn the rhubarb benefits and dosage + tips to use it safely.
What is Rhubarb?
Rhubarb is the name used to describe several plant species in the genus Rheum, native to China, Iran, Turkey, and India. Its underground storage organs – roots and rhizomes – have been used in traditional Chinese medicine since the third millennium BC [1, 2, 3].
Rhubarb has been traditionally used to heal a wide variety of issues such as constipation, fever, inflammation, and kidney failure. More recently, it was uncovered that Rhubarb can also alleviate symptoms of menopause and sepsis, a life-threatening response to infection [4, 5, 6, 7].
Rhubarb is known for its very sour, celery-like stalks, which vary in color, from pale pink to pale green. While the stalks can be used for cooking, the leaves are very poisonous. Some common varieties of rhubarb include [1, 7+]:
- Chinese rhubarb (Rheum officinale or Rheum palmatum)
- Garden or culinary rhubarb (Rheum rhabarbarum)
- Rhapontic rhubarb or false rhubarb (Rheum rhaponticum L.)
- Syrian rhubarb (Rheum ribes L.)
Snapshot
Proponents:
- May help with liver and kidney diseases
- Relieves menopausal symptoms and menstrual pain
- Boosts gut health
- Helps with sepsis and pesticide poisoning
- May support stroke recovery
- May lower cholesterol and blood pressure
Skeptics:
- Low-quality clinical evidence
- Mostly studied in China
- The leaves are toxic
- Can cause diarrhea due to laxative effect
- Not safe for pregnant women
Components
The most commonly used parts of the plant for medicinal purposes are the roots and rhizomes, which contain [6, 7+, 3+, 8]:
- Various plant pigments (anthraquinone compounds such as aloe-emodin, chrysophanol, emodin, and rhein)
- Laxative phenolic compounds (anthraquinone glycosides such as sennosides)
- Antioxidant phenolic compounds (catechins)
- Other phenolics (naphthalenes, glucose gallates)
- Polysaccharides (complex sugars)
- Stilbenes
- Tannins
Rhubarb contains toxic compounds known as salts of oxalic acid/oxalates, which are not broken down during cooking. These compounds are highly concentrated in the leaves, which should not be consumed [7].
Mechanisms of Action
Anthraquinone compounds such as sennosides are well-known laxatives that stimulate bowel movements. These compounds are not absorbed in the intestine and reach the colon unchanged. Gut bacteria then break them down into active metabolites, which reduce the amount of water the colon reabsorbs. This increases the fluid content and volume in the stool, easing constipation [3].
Other anthraquinone compounds such as aloe-emodin, emodin, and rhein have antibacterial properties. They may work by disrupting cell membranes of bacteria and their protein and energy production. Aloe-emodin can also act as a laxative [8].
They can also kill cancer cells and prevent metastasis by blocking excessive cell division [8, 9].
Stilbenes contribute to rhubarb’s cholesterol-lowering, antioxidant, and liver-protective effects [8].
Health Benefits of Rhubarb
Possibly Effective:
1) Liver Disease
Non-Alcoholic Fatty Liver Disease
In a clinical trial of 232 people, A Chinese herbal medicine containing rhubarb called Danning Pian improved non-alcoholic fatty liver disease symptoms and reduced ALT levels, a marker of liver damage [10].
Cirrhotic Ascites
A very common and serious complication of liver cirrhosis is a buildup of fluid in the abdominal area (cirrhotic ascites). In 92 people, Xiaozhang Tie, a Chinese herbal medication with rhubarb, moderately reduced abdominal swelling and overall symptoms. It was given alongside conventional treatment [11].
Genetic Disorders of the Liver
Infantile cholestatic hepatitis syndrome is a rare genetic disorder that causes bile build-up in the liver of newborns. Rhubarb was 89% effective at reducing jaundice, yellowish pigmentation of the skin that indicates bile buildup, in 64 infants [12].
2) Kidney Disease
Kidney Failure
In people with chronic kidney failure, levels of blood urea nitrogen (BUN) and creatinine are often high, as the kidneys struggle to eliminate waste products from the blood. Supplementation with 1 g/day of rhubarb normalized levels of BUN, creatinine, and other waste products in 48 patients [13].
Similarly, a Chinese herbal supplement containing rhubarb (Niaodujing) increased the removal of creatinine from the blood in a clinical trial of 105 people with chronic kidney failure [14].
Taking another Chinese herbal combination with rhubarb, Rheum E, helped slow the progression of chronic kidney failure in a clinical trial of 30 people. It was effective both alone and in combination with a drug for high blood pressure, captopril [15].
In another study, Chinese rhubarb with Captopril also normalized levels of a marker of kidney dysfunction (IL-6) in the urine of people with chronic kidney failure [16].
Combined with dialysis, a Chinese medication with rhubarb (Xinqingning) reduced the buildup of toxins in the blood; it helped slow the progression of chronic kidney failure in 57 patients. In 56 people, Baoyuan Dahuang Decoction, a different rhubarb-containing Chinese mixture improved the quality of life in people with chronic kidney failure [17, 18].
Diabetic Kidney Disease
Kidney disease is a common complication of diabetes. In 112 patients, rhubarb-containing Chinese herbal mixture (Tangshen Recipe) with insulin treatment was equally effective as conventional anti-diabetes drugs [19].
Kidney Inflammation
In a clinical trial of 32 people with kidney inflammation, a rhubarb-containing Chinese herbal remedy (Decoction of Qingre Huoxue) added to steroidal anti-inflammatory drugs improved kidney function better than the drugs alone. This remedy may allow for the dosage of steroids to be lowered while achieving equal anti-inflammatory benefits [20].
3) Menopausal Symptoms
In a clinical trial of 109 women approaching menopause, a rhapontic rhubarb supplement (ERr 731) reduced improved the quality of life and reduced symptoms such as the frequency and severity of hot flashes. Importantly, this supplement didn’t alter gynecological factors such as uterus health or bleeding [21].
Two more trials with over 200 women found similar benefits [22, 23].
ERr 731 also reduced anxiety from moderate-severe to slight, aside from reducing hot flashes in another clinical trial of 109 women transitioning to menopause [24].
4) Pancreas Inflammation
According to a meta-analysis of 16 clinical trials with over 900 people, rhubarb used with standard treatment is effective and safe for reducing pancreatic inflammation [25].
In a clinical trial of 126 people with severe inflammation of the pancreas, the use of Chinese rhubarb powder (15 g, 1 – 2x/day) with a specific nutrition plan lowered inflammation, disease severity, and liver and kidney damage [26].
A raw Chinese rhubarb solution (50 g/100 mL) helped reduce pancreas inflammation and abnormally high pancreatic enzyme levels in the blood after endoscopy, in a clinical trial of 500 people [27].
5) Herbicide/Pesticide Poisoning
A meta-analysis of 12 studies concluded that Chinese rhubarb has a beneficial effect on people with pesticide poisoning. The low quality of some studies is a potential drawback to the results [28].
10 g/day of Chinese rhubarb in combination with other herbs, stomach washing, and clay, was effective for herbicide poisoning. This protocol helped eliminate toxins, reduced their absorption, sped up recovery time, and prevented damage to multiple organs [29].
Chinese rhubarb combined with mineral powder and blood purification was more effective at treating severe herbicide poisoning than the standard procedure. Rhubarb reduced the duration of the hospital stay and the use of artificial breathing machines, helping the patients recover consciousness more quickly [30].
6) Gut Disorders
In a clinical trial of 30 people, Chinese rhubarb (10 g/day, fed nasally 3x/day) added to the normal treatment improved gut function [31].
In another trial of 89 critically-ill children, a Chinese herbal remedy (Fu’an Liquid) added to conventional drugs successfully reduced gut dysfunction. Even though a greater number of treated children survived, death rates were still high (30%) [32].
Infections
Syrian rhubarb syrup (2.5 – 5 mL) along with an antibiotic (ceftriaxone) reduced fever, diarrhea, and the duration of stomach pain in a clinical trial of 150 children with an intestinal infection. It also reduced the need for anti-fever medication [1].
Bleeding
Chinese rhubarb helped stop digestive tract bleeding in a study of 312 hospitalized people [33].
In a clinical trial of 60 people with digestive tract bleeding and fever, taking ground Chinese rhubarb (3 g, 3-4x/day) with ground Chinese ginseng (sanchi powder) boosted recovery. The combination worked by constricting the blood vessels, increasing platelets, improving platelet clumping, and reducing bleeding time [34].
Surgery Recovery
In a clinical trial of 360 people, a Chinese herbal concoction (Dannang Recipe No. 2) helped people undergoing gallbladder removal surgery recover gut functionality more quickly. It also reduced the length of the hospital stay and the need for IV fluids better than just antibiotics (Ceftizoxime sodium or Levofloxacin) [35].
7) Complications of Blood Poisoning (Sepsis)
In a meta-analysis of 15 clinical trials with 869 patients, rhubarb powder in combination with standard treatment improved gut dysfunction, inflammatory markers, and platelet count but didn’t reduce mortality [36].
In a study with over 1,000 patients with sepsis, Chinese rhubarb reduced fungal infections, especially when combined with adequate nutrition (via stomach tubes or IV) [37].
Similarly, 50 mL, 3x/day of a Chinese herbal (Hengyan medicine) used with conventional medication decreased levels of the inflammatory agents IL-6, IL-10, and TNF-α in a clinical trial of 45 people with sepsis [38].
A meta-analysis of 27 animal studies determined Chinese rhubarb may help reduce organ damage from blood poisoning. The benefits possibly derive from its antioxidant and anti-inflammatory properties [6].
8) High Cholesterol
Consuming 27 g/day of ground rhubarb stalks reduced total and LDL cholesterol by 8 – 9% in 10 men, but the study lacked a control group [39].
Similarly, in a clinical trial of 83 people with clogged arteries, a Chinese rhubarb preparation (50 mg/kg) lowered total and LDL cholesterol and also improved artery health [40].
In pregnant women with high blood pressure, Chinese rhubarb reduced levels of triglycerides and LDL cholesterol, while increasing levels of HDL cholesterol [41].
9) High Blood Pressure
A Chinese herbal with rhubarb (Jiangzhuoqinggan) was as effective as the standard drug, irbesartan, at reducing both systolic and diastolic blood pressure [42].
Pregnancy can temporarily cause high blood pressure. A low dose of Chinese rhubarb (0.75 g/day) was able to reduce the rates of this condition in 333 pregnant women at high risk [43].
10) Inflammation
Systemic inflammatory response syndrome (SIRS) causes widespread inflammation. In 78 people with SIRS, Chinese rhubarb powder added to the conventional treatment helped cure the disease, and reduced organ damage and deaths. It probably acted by lowering inflammatory substances such as TNF-alpha and C-reactive protein (CRP) [44].
Similarly, Chinese rhubarb extract (15 – 20 g, 2x/day) via enema or through a stomach tube reduced levels of pro-inflammatory substances in 57 SIRS patients [45].
In a clinical trial of 56 people, 10% Chinese liquid rhubarb along with conventional treatment lowered key inflammatory markers (CRP and IL-6) in stomach cancer patients [46].
11) Stroke Recovery
In a meta-analysis of studies with nearly 1,000 participants, Chinese herbal mixtures containing rhubarb, in addition to conventional medication, helped patients recover from strokes by reducing the severity of their post-stroke symptoms [47].
Rhubarb (5 – 10 g, 2 – 3x/day) given after surgery to stroke patients decreased markers of inflammation (complement 3, complement 4, and hypersensitive C-reactive protein), indicating improved healing [48].
The strength of the evidence from these trials is limited by small sample size, varying herbal formulas used, and the high risk of bias. Further research is warranted.
12) Mouth Ulcers (Canker Sores)
Chinese rhubarb extract (5%) was moderately effective at speeding the healing from recurring mouth ulcers in a clinical trial of 125 people [49].
13) Herpes Sores
In 145 patients, a sage and Chinese rhubarb (23 mg/g) topical cream had a similar efficacy as a common herpes medication (Zovirax) at healing herpes sores [50].
Insufficient Evidence:
No valid clinical evidence supports the use of rhubarb for any of the conditions in this section. Below is a summary of up-to-date animal studies, cell-based research, or low-quality clinical trials which should spark further investigation. However, you shouldn’t interpret them as supportive of any health benefit.
14) Acute Respiratory Distress Syndrome
Acute Respiratory Distress Syndrome causes serious lung inflammation. In a clinical trial of 80 people with this disease, 30 g/day of Chinese rhubarb was able to reduce fluid buildup in the lungs [51].
15) Menstrual Pain
In a clinical trial of 45 women, Himalayan rhubarb (1,260 mg, 2x/day) was equally effective at reducing menstrual pain as the painkiller mefenamic acid [52].
16) Radioprotection
Radiotherapy for lung cancer can cause severe adverse effects. In a clinical trial of 80 people, 20 mg/kg rhubarb reduced the incidence of lung toxicity, improved lung function, and reduced levels of inflammatory substances (TGF-beta1 and IL-6) [53].
17) Cognitive Function
Chinese rhubarb added to a Chinese remedy (Compound Tong Jiang Oral Liquid), improved memory and had antioxidant effects in senile people. However, the study doesn’t reveal crucial details such as sample size [54].
18) Weight Loss
A traditional Chinese herbal remedy that contains rhubarb (Xin-Ju-Xiao-Gao-Fang) at typical to low doses (10%) helped decrease body weight and insulin resistance in a clinical trial of 140 obese people [55].
A similar Chinese herbal remedy (Jiangzhuoqinggan) reduced waist circumference in a clinical trial of 240 people with high blood pressure [42].
However, two studies on rhubarb or its herbal combinations did find any weight loss benefits [56, 57].
More studies are needed to clarify the conflicting results. At this point, rhubarb can not be recommended as a complementary approach to weight loss
Animal and Cellular Research (Lacking Evidence)
No clinical evidence supports the use of rhubarb for any of the conditions listed in this section. Below is a summary of the existing animal and cell-based studies; they should guide further investigational efforts but should not be interpreted as supportive of any health benefit.
Bacterial Infections
The anthraquinones in rhubarb have antibacterial properties. One such compound, emodin, is effective against Staphylococcus aureus (even antibiotic-resistant strains), the bacteria that causes staph infections [8].
In rats, rhubarb extracts cleared an infection of H. pylori, the bacteria that causes ulcers. The extracts were effective against resistant strains, too [58].
Limitations and Caveats
Chinese rhubarb, which the majority of the studies used, is usually combined with other Chinese herbs and medicinal plants. The effects of rhubarb alone remain obscure.
Many of the Chinese rhubarb articles were conducted in China with Chinese people. The same effect might not be observed in other populations.
The health effects of the other forms of rhubarb have not been studied extensively.
Four meta-analyses examined rhubarb’s effects on herbicide poisoning, stroke recovery, pancreatic inflammation, and blood poisoning (sepsis). All four analyses noted that the examined studies had poor methodological quality [28, 36, 47, 25].
Side Effects & Precautions
This list does not cover all possible side effects. Contact your doctor or pharmacist if you notice any other side effects. In the US, you may report side effects to the FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada, you may report side effects to Health Canada at 1-866-234-2345.
Rhubarb rhizome and root are likely safe in the amounts present in food and possibly safe as nutritional supplements, used in adequate amounts. The reported side effects include [10, 3]:
- Diarrhea
- High liver enzymes
- Skin rash
- Changes in urine color
Pregnant women should avoid this herb in all forms due to its potent laxative effect [59].
Drug Interactions
Supplement-drug interactions can be dangerous and, in rare cases, even life-threatening. Always consult your doctor before supplementing and let them know about all drugs and supplements you are using or considering.
Because rhubarb has a laxative effect, please discuss with your doctor before taking it with any medications. Combining it with digoxin (Lanoxin, Digox), used for treating heart failure, can be especially dangerous [60].
Is Rhubarb Poisonous?
While many plants contain oxalates/oxalic acids in varying amounts, rhubarb leaves contain very high concentrations of these toxic compounds, making them unsafe for consumption. However, the stalks are low in oxalates and safe to eat. Both Chinese and common rhubarb, the most common types, are generally considered safe for consumption [7, 59].
Supplementation
Rhubarb supplements have not been approved by the FDA for medical use. In general, regulatory bodies aren’t assuring the quality, safety, and efficacy of supplements. Speak with your doctor before supplementing.
Forms
Rhubarb can be found in various forms, usually made from the roots and rhizomes of Chinese rhubarb [3, 4]:
- Capsules/Tablets
- Powder
- Dried root pieces
- Tea
- Tinctures
- Infusions
- Extracts
- Traditional Chinese Medicine combination remedies (most common)
Dosage
The below doses may not apply to you personally. If your doctor suggests using rhubarb, work with them to find the optimal dosage according to your health condition and other factors.
The doses for rhubarb widely vary. Clinical trials used doses ranging from 50 mg to 50 g/day, depending on the disease, type of extract, and other factors.
For Chinese rhubarb in a crude powder form, a common dosage is 10-30 g/day.
The dosage of ERr 731 (rhapontic rhubarb) is 1 tablet/day.
Takeaway
Rhubarb has been used for centuries and is especially important in Traditional Chinese Medicine (TCM), which considers it a vital remedy for various diseases. Scientific studies have confirmed numerous benefits that range from gut, liver and kidney protection to lowering inflammation and cholesterol. Still, most benefits lack solid clinical evidence.
Chinese rhubarb is often combined with other herbs and dietary changes to achieve synergistic effects in TCM. Common rhubarb may relieve menstrual pain and menopausal symptoms. The parts of rhubarb medicinally used – rhizome and roots – are generally very safe and cause few side effects.
It’s also important to keep in mind that Rhubarb has laxative action, which is desired in some cases but may cause discomfort in others. The leaves of Rhubarb are toxic and should not be consumed. Pregnant women should avoid it while others should consult their doctor before supplementing.