How does it feel?
Rhubarbs taste is predominately bitter and astringent. A slightly acidic or sour taste may follow along with rich earthy and mildly smoky pungent qualities.
What can I use it for?
Rhubarb is used predominantly in the treatment of occasional constipation taken short term as a stimulant laxative. It does however have a limitation for this use as it is only symptomatic treatment, and it must be used as part of an approach to treat the underlying cause where the problem is chronic or reoccurring.
A herbalist will always give a holistic assessment of their patients with ongoing or recurring constipation, as there may be a number of different reasons why this symptom has occurred and that treatment needs to address that unique set of circumstances to deliver an effective, long term treatment.
For example; there may be dietary or lifestyle considerations or other more organic causes to do with the physiological function of the intestines. This may include poor gut health or enzymatic activity. Each cause would have to be addressed individually.
Rhubarb is however an extremely effective stimulant laxative for the symptomatic treatment of constipation. It also has multiple other benefits. Whilst it removes debris from the digestive tract it also exerts a detoxifying action on the tissues via an astringent action on the mucosa of the digestive system.
It is worth noting that there are a number of safety considerations including herb/ drug interactions and contraindications for this plant. It is best to consult a herbalist before using rhubarb species if in doubt.
Rhubarb may be used at the recommended dose for a maximum of 2 weeks as it can cause habituation of the bowel. If symptoms do not start to improve within 5 days- seek medical attention.
Into the heart of Rhubarb
In old Western medicine Rhubarb was used as a purgative of all humours- blood, yellow bile, black bile, and phlegm. Its actions detoxify the blood systems through its bitter action on the liver. Bitter herbs like rhubarb directly support liver function. This improved eliminatory action can have widespread effects throughout the body to reduce systemic inflammation which is why rhubarb is sometimes indicated for rheumatic conditions (5).
In Ayurvedic medicine there is a different model and understanding of what each organ does and how they connect. Ayurveda has its own unique philosophy and understanding of bodily systems and herbal qualities that has been built up over thousands of years of empirical observation. In Ayurveda there are three doshas: vata, pitta and kapha. Their energies are believed to circulate in the body and govern physical, mental and emotional characteristics. They are described as follows; vatacontrols basic bodily functions as well as the mind, pitta governsmetabolism, digestion and hormones linked to appetite and finally kapha is responsible for strength and stability, muscle growth, weight and the immune system.
In Ayurveda, rhubarb is understood to have light, dry and cooling qualities. Its dosa effect is PK- V+ meaning that it reduces pita (heat) and kapha (congestion). It is said to be an invaluable medicine for intestinal congestion, bleeding and blood toxicity. It directs the flow of vata via its downward effect on the lower intestine as a laxative (3).
The common indications for high kapha and pita may be seen as manifestations of damp-heat symptoms in the gut. There may be dysentery or blood and mucus in the stool. It is important to note that blood in the stool requires immediate medical investigation. If this symptom occurs refer to a general practitioner to identify the cause (3).
Rhubarb was originally imported from China and Tibet as R. palmatum and R. officinale. Therefore, the ancient uses of this medicine will have been carried forwards in traditional Chinese medicine.
It has a long-standing use as an antibacterial, anti-inflammatory and anticancer medicine in China. It is thought to have been a valuable adjunct in the clearing of tumors and toxins from the bowel. This tradition of use still stands today in TCM as well as in the Ayurvedic use of rhubarb.
Traditionally rhubarb was ground in vinegar. This would be used externally as a poultice for the treatment of freckles, eczema, and inflammations. Internally, it is used to relieve flatulence, and to treat stomach and intestinal weakness, jaundice, ascites, inflammation of liver and spleen, cough, asthma and bleeding. It is also referenced to have been traditionally used to relieve renal and urinary bladder pain.
What practitioners say
Rhubarb is a stimulating laxative which also works as a purgative and astringent to the digestive system. This enhancing action on the excretory function of the gastrointestinal tract combined with rhubarbs astringency and antiseptic properties also exerts a deeply cleansing action on the mucous membranes. This takes strain off of the liver and gall bladder by supporting elimination in the localised digestive tissues, removing viscid mucus and debris. Lower doses of rhubarb may be used as a tonic hepatic, whereas larger doses are more generally cathartic or purging (2).
There is also a dose dependent use of rhubarb for diarrhoea. The anthraquinones purge the bowel, exerting a laxative effect in higher doses. Whereas lower doses provide the correct level of tannins to astringe and tone in the treatment of mild diarrhoea (3).
The use of rhubarb for diarrhoea is less common. It is primarily used as a stimulant laxative. Rhubarb has a number of unique compounds which are responsible for these effects. The primary compound hydroxyanthracene and its derivatives possess a laxative effect. Its β linked glucosides are converted in the large intestine by the gut bacteria into anthrones.
At the higher dosage, these compounds enhance motility by stimulation of peristaltic contractions in the large intestine. They are also thought to stimulate the intestinal fluids (i.e. mucus) which helps to improve the movement of stool through the bowel (1).
There is a delay of around 8 hours after taking rhubarb before the laxative effects occur. This is due to the transit time between ingestion and metabolic conversion of active compounds in the colon.
The liver stimulating bitter action of rhubarb makes it also useful for conditions of the liver and gallbladder. This is sometimes used by herbalists as part of an approach to treat cirrhosis or acute hepatitis where there is liver congestion and heat. It is also an effective cholagogue and may be used as part of an integrated approach for the elimination of small gall stones (<0.5mm) (3).
Rhubarb has cellular protective action due to its antioxidant content. It also has strong potential to be used as part of an integrated approach with other herbs and interventions in certain forms of cancer. There has been some promising research that demonstrates that extracts of rhubarb have an inhibiting effect on lung adenocarcinoma, breast and cervical cancer cells. Rhubarb and its extracts have been shown to be anti-proliferative, anti-metastatic and apoptotic (1).
In vitro studies have identified a strong inhibition of Helicobacter pylori bacteria using a water based extract of rhubarb. Rhein is a constituent in rhubarb that in combination with antibiotics ampicillin and oxacillin have synergistic effects against methicillin-resistant Staphylococcus aureus strains (MRSA). Ethanol extracts also demonstrated antiviral activity against Herpes simplex virus, preventing cellular attachment and penetration. Rhein isolated from rhubarb has also been exhibited antimicrobial and anti fungal activity against Candida albicans and Bacteroides fragilis (1,6,7).
A randomised controlled study was carried out to investigate the efficacy of R. Officinale for the treatment of incomplete intestinal obstruction. The subjects were randomised into a treatment group and a control group with 29 cases in each group. The control group was given an enema laxative, while the treatment group received R. officinale in powdered form internally in addition to an enema. The time of flatulence, bowel movements, and abdominal bloating intensity was observed. The treatment group was observed to have significantly improved scores from that in the control group. The study concludes that R. officinale is an effective medicine in treating incomplete intestinal obstruction (4).
Rhubarb and its extracts have been shown to have anti proliferative, anti-metastatic and apoptotic properties. These actions have been demonstrated using in-vitro studies on human chronic cyelocytic leukaemia K562 cells, pancreatic cancer cells, cervical cancel help cells, hepatoma cells neuroblastoma cells and tongue squamous cancel cells (1).
Several phenolic compounds in rhubarb were found to have cytotoxic effects via induction of apoptotic cell death in both human oral and lung squamous cell carcinomas.
A Cochrane database systemic review of clinical trials found R. officinale had a concurrently positive effect on serum creatinine and BUN on of patients with chronic kidney disease compared to those with no treatment (5).
Rheum are robust rhizomatous herbaceous perennials with large, simple or palmately lobed leaves and tall leafy stems bearing large panicles of tiny flowers. Its leaves are large and scalloped with a stout hollow stem and fine white hairs at the nodes. It has tall panicles of white flowers which grow from 2m long stems in spring. These are followed by large winged seeds in late summer/ autumn.
Rhubarb spp R. palmatum and R. officinale are used interchangeably in herbal medicine. Note that garden rhubarb is not the same plant as discussed in this monograph, so do not confuse them.
Other names: Rheum palmatum is also known as Turkey rhubarb, East Indian rhubarb, or palmate rhubarb. Rheum officinale is also known as Indian rhubarb, Tibetan rhubarb, or medicinal rhubarb.
Rhubarb is not recommended for use during pregnancy and lactation. It is also not recommended for use in children under 10 years of age.
Hypokalaemia (resulting from long term laxative abuse) potentiates the action of cardiac glycosides and interacts with anti-arrhythmic drugs or with drugs which induce reversion to sinus rhythm (e.g. quinidine).
Concomitant use with other drugs inducing hypokalaemia (e.g. thiazide diuretics, adreno-corticosteroids and liquorice root) may aggravate electrolyte imbalance (1). It is not advised to use liquorice root or the former mentioned medications alongside rhubarb.
Rhubarb should not be used in medical preparations in cases of intestinal obstruction and stenosis, atony, inflammatory bowel disease (i.e. Chron’s disease, ulcerative colitis), appendicitis, abdominal pain of unknown origin, severe dehydration states with electrolyte depletion (1).
- Dried or powdered
For use as a stimulant laxative the dosage may vary. The advice is to use the smallest amount required to produce a comfortable soft-formed motion. Build up from the lowest recommended dose for the desired effect.
Dried/ powdered: 0.5g is astringent for treatment of diarrhoea. Whereas 3g+ is used for laxative and purgative effects. This may be taken daily.
Decoction: A similar scale of dosage using dried or powdered root may be used as a decoction. Simply add the root to hot water, simmer for 10 minutes strain and drink.
Tincture (1:3 at 25%): Take between 1- 6ml a day.
Please note: Stimulant laxatives should not be used for periods of more than 2 weeks (unless advised by a healthcare practitioner).
Plant parts used
- Hydroxyanthracene derivatives (3- 12%) – consisting mainly of 60= 80% of mono and diglucosides of Rhein, chrysophanol, aloe-emodin, physcion, and emotion. Smaller amounts of dianthrone glycosides (sennosides)
- Gallotannins (5%)
- Volatile oil (traces) (1)
Rhubarb spp are native to China and Tibet. They are found in fresh water habitats and may be found growing by streams in scrub and rocky places.
According to the IUCN Red List of Threatened Plants Status:
Habitat loss and over harvesting from the wild are two of the biggest threats faced by medicinal plant species. There are an increasing number of well known herbal medicines at risk of extinction. We must therefore ensure that we source our medicines with sustainability in mind.
The herb supplement industry is growing at a rapid rate and until recent years a vast majority of medicinal plant produce in global trade was of unknown origin. There are some very real and urgent issues surrounding sustainability in the herb industry. These include environmental factors that affect the medicinal viability of herbs, the safety of the habitats that they are taken from, as well as the welfare of workers in the trade.
The botanical supply chain efforts for improved visibility (transparency and traceability) into verifiably sustainable production sites around the world is now certificated through the emergence of credible international voluntary sustainability standards (VSS). Read our article on Herbal quality and safety: What to know before you buy to learn more about what to look for and questions to ask suppliers about sustainability.
Herbal Medicines are often extremely safe to take, however it is important to buy herbal medicines from a reputed supplier. Sometimes herbs bought from unreputable sources are contaminated, adulterated or substituted with incorrect plant matter.
Some important markers for quality to look for would be to look for certified organic labelling, ensuring that the correct scientific/botanical name is used and that suppliers can provide information about the source of ingredients used in the product.
A supplier should be able to tell you where the herbs have come from. There is more space for contamination and adulteration when the supply chain is unknown.
How to grow
Rhubarb spp grow best in humus-rich, acidic to neutral, moist soil. They should be positioned in full sun to partial shade.
- Propagate from seed or division in spring. Sow seeds in seed compost or plant root clumps or plantlet into small pots.
- Splitting or planting a root division is a way to refresh older plants that have fulfilled their optimum growing potential. You may take pieces of mature root systems, and then transplant, water and fertilise these for more young plants. However do not divide plants that have been in the ground for less than three years.
- This ornamental rhubarb is an architectural plant that demands space. Plant it out in a sunny location with adequate space for a wide spread of its palmate leaves. Cut down flowering stems after blooming and mulch annually to conserve moisture.
- Bernat (2019). Rhei radix (Rhubarb) – Online consultation. [online] ESCOP. Available at: https://escop.com/rhei-radix-rhubarb-online-consultation/ [Accessed 26 Apr. 2023].
- Hoffman, D. (2003). Medical Herbalism: The Science Principles and Practices Of Herbal Medicine. Hardback (1st Edition). Independently published
- Pole, S. (2013). Ayurvedic medicine : the principles of traditional practice. London ; Philadelphia: Singing Dragon, Cop.
- Yu, M. (2016). Clinical Study onDa Huang (Rheum Officinale) Powder Application at Shenque (CV 8) for Incomplete Intestinal Obstruction. Shanghai Journal of Acupuncture and Moxibustion, [online] pp.541–542. Available at: https://pesquisa.bvsalud.org/portal/resource/pt/wpr-487382 [Accessed 3 May 2023].
- Akbar, S. (2020). Rheum officinale Baill.; R. palmatum L. (Polygonaceae). doi:https://doi.org/10.1007/978-3-030-16807-0_158.
- Gou K, Sun L, Lou W, Ling C, Wang Y.Fourcompoundsofanthraquinone in Rheum officinale on Helicobacter pylori inhibition. ZhongguoYaoxue Zazhi (Beijing) 1997;32:278-80.
- Bae EA, Han MJ, Kim NJ, Kim DH. Anti-Helicobacter pylori activity of herbal medicines. Biol Pharm Bull 1998;21:990-2. https://doi.org/10.1248/bpb.21.990