Rhubarb

Rhubarb (da huang, 大黄), also known as Radix et Rhizoma Rhei, refers to the root or rhizome of Rheum palmatum L., or R. tanguticum Maxim. ex. Balf. or R. officinale Baill, which are perennial herbaceous plants that belong to the Rhubarb family.

Used medicinally by the Chinese for thousands of years, Rhubarb is documented in The Divine Farmer’s Materia Medica that is compiled over 2700 years ago. Many people used Rhubarb as a laxative, and it was one of the first Chinese medicines to be imported from the West from China. 

During Islamic times, Rhubarb was imported along the Silk Road to Europe from ports in Aleppo and Smyrna, where it became known as ‘Turkish Rhubarb’. The plant was more expensive than cinnamon, opium and saffron back then. Its high prices led to efforts for cultivating the plant on closer European soils.

In Traditional Chinese Medicine (TCM), Rhubarb falls under the category of ‘Purgative herbs that drain downward’. Such herbs can treat constipation by removing excess Heat in the intestines and stomach. Cold in nature, Rhubarb can help individuals with too much Heat in their body, such as those experiencing a yang excess or a yin deficiency, to restore a harmonious yin-yang balance.

Bitter in taste, Rhubarb can cleanse the body by clearing Heat, drying Dampness and promoting elimination via urination or bowel movements. In particular, Rhubarb targets the Spleen, stomach, large intestine, Live and pericardium.

Traditional Chinese Medicine (TCM) shows that Rhubarb has the following health benefits.

Rhubarb has unblocking and descending properties, and can thus remove accumulations in the body through its purgative effects. For example, Rhubarb can relieve constipation caused by accumulation, especially accumulation of Heat accompanied by symptoms like high fever, restlessness and abdominal distention. Rhubarb can be combined with other bowel-relaxing purgatives and distention-relieving herbs to enhance its effectiveness.

For constipation caused by the accumulation of Cold, Rhubarb can be combined with interior-warming herbs to enhance its treatment effects. For constipation caused by the accumulation of Heat accompanied by qi deficiency and Heat deficiency, Rhubarb can be combined with qi-replenishing and blood-nourishing herbs to enhance its effectiveness. For food stagnation, Rhubarb can be combined with digestants. 

By driving stasis downwards and clearing stasis-Heat, Rhubarb is indicated for many kinds of diseases caused by stasis too. For instance, Rhubarb is used for abdominal stasis mass, amenorrhea and dysmenorrhea caused by stasis.

Also, Rhubarb can clear Heat, purge fire, cool blood and stop bleeding. For example, Rhubarb can be combined with Heat-clearing, fire-purging, toxicity-removing and swelling-relieving herbs to treat blood-shot eyes, headache, sore throat, throat pain and swollen gums caused by the up-flaming of zang fu fire-Heat. For hematemesis, epistaxis and hemoptysis caused by the irregular circulation of blood due to fire-Heat, Rhubarb can be combined with Heat-clearing and bleeding-stopping herbs to enhance its effects.

Rhubarb is indicated for both internal and external sores and abscesses with swelling pain too. For example, Rhubarb can treat intestinal abscess with abdominal pain, as well as burns caused by hot liquid or fire. In addition, Rhubarb can clear Heat and resolve Dampness to treat Damp-Heat accumulation, manifested as symptoms such as jaundice and stranguria.

The recommended daily dosage of Rhubarb is 10 -15g, when used as a decoction. As fresh Rhubarb is stronger in its purgative properties than processed Rhubarb, unprocessed Rhubarb is usually used to treat constipation. 

On the other hand, Rhubarb stir-baked with alcohol is weaker in purgation, but is usually used to resolve stasis and relieve stagnant blood syndromes or fire-Heat in the upper body. Carbonized Rhubarb is used for bleeding syndromes.

For burns caused by hot liquid or fire, Rhubarb can be ground into powder, mixed with sesame oil then applied on the affected area.

Rhubarb and its supplements can be found in herbal stores and Asian specialty markets.

Rhubarb should not be used by individuals experiencing qi deficiency or blood deficiency without accumulation or blood stasis, weak stomach qi, invasion of External pathogens, Spleen and stomach deficiency Cold, no Heat or fire symptoms, intestinal obstructions, renal stones, abdominal pain of unknown origins, gout or haemorrhoids.

Individuals experiencing pregnancy or menstruation, and postpartum women should use this herb with extreme caution. Children under the age of 12, dehydrated individuals and people with electrolyte imbalances should use this herb with caution too.

Some side effects associated with Rhubarb include nausea, vomiting, dizziness, abdominal cramps and jaundice.

Here is a summary for Rhubarb:

• Herb name (Chinese): 大黄
• Herb name (Pin Yin): dà huáng
• Herb name (English): Rhubarb
• Herb name (Botanical): Radix et Rhizoma Rhei
• Origin of species: Rheum palmatum L.; Rheum tanguticum Maxim. ex Balf.; Rheum officinale Baill.
• Part(s) of herb used: Root and rhizome
• Geo-specific habitat(s): Qinghai, Gansu, Sichuan
• Taste(s) & Properties: Bitter; Cold; Administrates the Spleen, Stomach, Large Intestine, Liver and Pericardium Meridians
• Actions: Eases symptoms related to severe constipation; Eases inflammatory conditions such as external skin rashes, carbuncles, scalds or burns, sore throats or painful eyes; Relieves menstrual pain or pain experienced after delivery by removing blood stasis; Eases symptoms of jaundice and painful urination

Qi, J. H., Dong, F. X., Wang, K., Zhang, S. Y., Liu, Z. M., Wang, W. J., … & Wang, X. L. (2022). Feasibility analysis and mechanism exploration of Rhei Radix et Rhizome− Schisandrae Sphenantherae Fructus (RS) against COVID-19. Journal of Medical Microbiology, 71(5), 001528. [Accessed on 20th June 2023]

Ren, X., Shao, X. X., Li, X. X., Jia, X. H., Song, T., Zhou, W. Y., … & Fu, X. J. (2020). Identifying potential treatments of COVID-19 from Traditional Chinese Medicine (TCM) by using a data-driven approach. Journal of Ethnopharmacology, 258, 112932.[Accessed on 20th June 2023]