Herb reference entry
Rhubarb Root / Rheum Root
Rhubarb Root / Rheum Root
Rheum palmatum L.
Reviewed by Kuda, September 2, 2026 - Editorial policy
OVERVIEW
What This Record Covers
Rhubarb Root, called Da Huang, is the dried rhizome and root of Rheum palmatum and selected Rheum species, large perennial herbs of the knotweed family (Polygonaceae) that grow in cool mountain regions of western China and Tibet. The medicinal material is the thick, yellow-brown root and rhizome with a characteristic yellow or reddish internal pattern, harvested from older plants, cleaned, and dried for use. In trade it appears as root pieces, slices, powder, granules, and combined formulas, and species, root versus rhizome, and anthraquinone content are key identity details. The plant is botanically distinct from the culinary rhubarb stalks eaten as fruit.
- English name
- Rhubarb Root / Rheum Root
- Latin name
- Rheum palmatum L.
- Traditional category
- Purgative
- Nature
- Cold
- Flavor description
- Bitter
- Record identifier
- dahuang
IDENTIFICATION
Identification and Image Notes
Rhubarb material is yellow-brown outside with a yellow or reddish internal pattern, and species, root versus rhizome, and anthraquinone content are key identity details. The cut surface shows a distinctive marbled pattern of yellow and reddish streaks, and the material is firm, dense, and slightly gritty when crushed. The patterned interior is an orientation clue, but the species and the batch record should be confirmed with the label, and processed forms should be stated on the product.
Images are for orientation only, not definitive species authentication; confirm species, part, source, and labeling with a qualified professional or authoritative monograph.
TRADITIONAL CONTEXT
Traditional Use in Context
Traditional records discuss Rhubarb for draining accumulation, clearing heat, blood movement, and bowel-related historical language, and it is a defining ingredient of classical purgative formulas such as Da Cheng Qi Tang, where it is paired with Mirabilite and Magnolia Bark for severe constipation with heat, and of heat-clearing and blood-moving combinations, with wine, vinegar, and charcoal processing recorded for different roles. Classical texts describe it for constipation with heat and for blood-moving presentations, always within a pattern-based framework. The draining vocabulary is historical, and severe abdominal pain, vomiting, or blood in stool requires medical care rather than self-treatment with a purgative.
PROCESSING CONTEXT
Raw Material, Processing, and Product Form
Raw, wine-processed, vinegar-processed, and charcoal-treated forms are recorded separately, and the traditional effect and safety discussion change with processing and product concentration. Each processed form is a separate record.
The same name can cover a raw material, decoction piece, powder, extract, or finished product, so record the labeled form rather than assuming it; see the safety review for the questions to ask.
SAFETY REVIEW
Safety Boundaries
Review diarrhea, dehydration, electrolyte loss, kidney disease, pregnancy, obstruction, and long-term use, and check for interactions with diuretics or medicines affecting electrolytes. Severe abdominal pain, vomiting, or blood in stool requires medical care, and repeated laxative use should be avoided without professional review.
This record is not a dose recommendation; risk depends on identity, preparation, amount, duration, contamination, other medicines, and health conditions — a traditional or “natural” label cannot establish safety. For the full framework, read the Chinese Herbal Medicine Safety Review.
COMPARISON
How This Entry Differs
Compare Rhubarb Root with Hemp Seed and Cassia Seed for bowel language, plant part, cooling strength, and very different exposure risks. Rhubarb is the strongest and most strictly monitored of the three bowel-related records. The different processed forms, from the raw purgative to a charcoal-treated record, show why the labeled form matters more here than for most roots.
Use the related-entry links below to compare identity, part, processing, and safety boundaries — similar categories do not make materials interchangeable.
STUDY METHOD
New to these entries?
Read the four-step method in How to Read a Herb Entry before comparing materials.
