Cascara - Rhamnus purshiana

Family: Rhamnaceae - Buckthorn Family



Other Uses

Medicinal Uses

"This herb, which has had a place in the U.S. Pharmacopoeia since 1890, is one of the most popular herbal medicines in the world. It is included in many over-the-counter laxatives and is prescribed more than 2.5 million times a year."[PDBHM]

"As well as its uses as a laxative, it is taken internally in the treatment of digestive complaints, haemorrhoids, liver problems and jaundice[238]." [PFAF] "Described in folk medicine, as an internal treatment for diabetes and used externally for skin irritations (6)." [WHO,2,1999]



General "Deciduous shrub or small tree up to 10 m tall..."[IFBC][E-flora] "thin, smooth, silver-grey, numbingly bitter bark." [PCBC2004]
Flowers "...stalked cluster of 8-25 male and/or female flowers; petals 5..."[IFBC][E-flora] "...greenish, inconspicuous, bearing both stamens and pistils..." [HNW] "...stamens: 8-50 in stalked, umbrella-shaped clusters in the axils of leaves." [PCBC2004]
Fruits Berries. Black to purplish-black; seeds 3.[IFBC] [E-flora]
Leaves "Alternate, egg-shaped to broadly elliptic..."[IFBC][E-flora] "...may seem almost opposite on new growth...young plants may retain their foliage over mild winters".[PCBC2004]
Habitat Streambanks, thickets, woodlands and forests.[IFBC][E-flora] Open woods.[HNW]
Range Common in SW B.C.[IFBC][E-flora] "...often shady sites...swampy bottomlands with red alder..."[PCBC2004]
Status Native. [E-flora]


Medicinal Use:


CascaraRhamnus purshiana [Dukephyt]

Part: Seed PPM
Protein 25% [15028] Riboflavin (mg) - Calcium (mg) -
Part: Bark PPM & %
Food Energy (Kcal) 2370 ppm [PED] Ash 1.9-6.7% [PED98] Potassium .11-.40% [PED98]
Water 72.3% [PED98] Thiamine (PPM) 0 [PED98] Magnesium (PPM) 440-1590 [PED98]
Protein 2.52-9.1% [PED98] Riboflavin (PPM) 0 [PED98] Calcium (PPM) 4100-14800 [PED98]
Fat .89-3.2% [PED98] Niacin (PPM) 8-29 [PED98] Phosphorus (PPM) 158-570 [PED98]
Carbohydrate (PPM) 22.4-80.9% [PED98] Sugars 1.39-5% Sodium (PPM) 26-93 [PED98]
Crude Fiber 31% [PED98] Dietary Fiber 56% [PED98] Iron (PPM) 6.4-23 [PED98]
Chromium (PPM) 0.2-0.6 Manganese (PPM) 0.4-1.4 [PED98] Selenium (PPM) 0.3-1.1 [PED98]
Cobalt (PPM) 3.2-11.6 [PED98] Tin (PPM) 1.4 - 5.1 [PED98] Silicon (PPM) N/A [PED98]
Zinc N/A [PED98]


Antibacterial (1; HH2); [HMH Duke]
Antiherpetic (1; APA; HH2); [HMH Duke]
Antileukemic (1; APA); [HMH Duke]
Antiseptic (1; APA; DEM); [HMH Duke]
Antispasmodic (f; PED); [HMH Duke]
Antiviral (1; APA; HH2); [HMH Duke]
Bitter (1; PED); [HMH Duke]
Cathartic: "Described in pharmacopoeias and in traditional systems of medicine as a cathartic".[WHO,2,1999] Bark.[HNW]
Depurative (f; DEM); [HMH Duke]

Diuretic (f; CRC); [HMH Duke]
Emetic (1; APA; DEM); [HMH Duke]
Fungicide (1; FNF); [HMH Duke]
Hepatotonic (f; PED); [HMH Duke]
Hydragogue (1; PH2); [HMH Duke]
Laxative (2; APA; FNF; HH2; PED; PNC; PH2; SKY); [HMH Duke]
Peristaltic (2; PNC); Poison (f; DEM); [HMH Duke]
Prostaglandigenic (1; PH2); [HMH Duke]
Sunscreen (f; APA); [HMH Duke]
Tonic (f; DEM; PNC). [HMH Duke]


"The fresh bark of cascara sagrada contains free anthrones," anthrone - glycosides, "aloe - emodin - O - glycoside, and dianthrones... During the drying process, the free anthrones and their corresponding O - glycosides are diminish the emetic properties of the bark extract. Bacterial...activity converts the inactive anthraquinone - O -glucosides into the pharmacologically active aglycon anthrones." [TNS]

CascaraRhamnus purshiana - Plant [Dukephyt]
Anthraquinone -> glycoside Aloin Plant (Duke1992A)[Dukephyt]
Anthraquinone -> Cascarin Plant (Duke1992A)[Dukephyt]
Anthraquinone -> Emodin Plant (411)[Dukephyt]
Anthraquinone -> O-glycoside Emosin-oxanthrone Plant (CAN)[Dukephyt]
Anthraquinone -> Isoemodin Plant (LAF)[Dukephyt]
Fatty Acid -> Linoleic-Acid Plant (Duke1992A)[Dukephyt]
Fatty Acid -> Myristic-Acid Plant (Duke1992A)[Dukephyt]
- Oxanthrone Plant (Duke1992A)[Dukephyt]
- Purshianin Plant (Duke1992A)[Dukephyt]
- Quebrachol Plant (Duke1992A)[Dukephyt]
- Rhamnol Plant (Duke1992A)[Dukephyt]
- Rhamnustoxin Plant (Duke1992A)[Dukephyt]
trihydroxybenzoic acid -> Syringic-Acid Plant (CAN)[Dukephyt]
polyphenol -> Tannic-Acid Plant (Duke1992A)[Dukephyt]
CascaraRhamnus purshiana - Bark[Dukephyt]
Anthraquinone -> glycoside Cascarosides Bark 4-6.5%(Duke1992A)[Dukephyt]
Anthraquinone -> glycoside Barbaloin Bark (LAF 15285)


- Anthranol Bark (14650)[Dukephyt]
Phenolic -> Anthroquinones Bark 6-10% (LAF)[Dukephyt]
- Ascorbic Acid Bark 0 (PED98)[Dukephyt]
terpenoid -> Beta-carotene Bark 13-46 ppm (PED98) [Dukephyt]
- Casanthranol Bark (Duke1992A)[Dukephyt]
- Cassiamin-C Bark 120ppm (15286)[Dukephyt]
anthraquinone -> Chrysophanic-Acid AKA (Chrysophanol) Bark (LAF 15289 15286 19313 15285)[Dukephyt]
C-glycosides -> Deoxybarbaloin AKA (Chrysaloin) Bark (Duke1992A)[Dukephyt]
- Emodin-Anthrone Bark (19313)[Dukephyt]
- Frangulaemodin Bark (15285 16729)[Dukephyt]
- Frangulin Bark (LAF PED)[Dukephyt]
Anthraquinones -> Palmidins Bark (411)[Dukephyt]
anthraquinone derivative -> Physcion Bark (15289 19313 15286 15285)[Dukephyt]
- Resins Bark (LAF)[Dukephyt]
polyphenol -> Tannins Bark (LAF)[Dukephyt]


"Succeeds in any reasonably good soil in sun or partial shade[11, 238]. This species is hardy to at least -15°c[238]. Closely related to R. frangula[11]. This species is cultivated as a medicinal plant in N. America[57, 60, 61] and is also collected from the wild[238]. It is becoming rare in the wild because of over-collection[238]. The flowers are produced in small clusters on shoots of the current year's growth[82]. A good bee plant[94]. The species in this genus are notably resistant to honey fungus[200]." [PFAF]


"Seed - best sown in the autumn in a cold frame. Stored seed will require 1 - 2 months cold stratification at about 5° and should be sown as early in the year as possible in a cold frame or outdoor seedbed[200]. Prick out the seedlings into individual pots when they are large enough to handle, and grow them on in the greenhouse or cold frame for their first winter. Plant them out in late spring or early summer of the following year. Cuttings of half-ripe wood, July/August in a frame[113]. Cuttings of mature wood of the current year's growth, autumn in a frame. Layering in early spring[4]."[PFAF]

Rhamnus - Buckthorn

Family: Rhamnaceae - Buckthorn Family

Shrub, small tree, < 10 m. Stem: branches alternate, stiff or flexible; twigs generally not thorn-tipped; winter bud scales present, generally ± 3 mm. Leaf: scattered along branches or clustered on short-shoots, deciduous or evergreen; stipules generally deciduous; petioles generally glabrous; blade veins prominent or not. Inflorescence: flowers 1 or in cyme-like clusters in axils. Flower: unisexual (bisexual), generally on separate plants, generally < 3 mm; hypanthium bell-shaped to cup-like, 2–3 mm wide; sepals 4–5, thin, spreading, not keeled adaxially; petals 0 or 4–5; disk thin, adhering to hypanthium; ovary appearing superior or partly inferior, chambers 2–4, each 1-ovuled, style 1, stigma 2–4-lobed. Fruit: drupe, 2–3[4]-stoned.
110 species: temperate, few tropics; some of value in medicine or as dyes. (Greek: name for plants of this genus) [Bolmgren & Oxelman 2004 Taxon 53:383–390] W.H. Brewer collected Rhamnus cathartica L., considered invasive in parts of United States, in 1861, but it apparently never naturalized. Other taxa in TJM (1993) moved to Frangula. [Jepson]

Local Species;

  1. Rhamnus purshiana - Cascara [TSFTK][PCBC]

The Alder Buckthorn, Rhamnus Frangula, also a native of Europe, is used for "making the best charcoal for the finest gunpowder." It has been introduced in a few swampy places about New York. Its fruit is disagreeable.[EWP]

"Both R. californica and the closely related R. purshiana have been referred to as cascara sagrada. Today, however, the name cascara sagrada is used most often to designate R. purshiana. Although both species can be used as a laxative, R. purshiana is preferred."[Nyerges]


Page last modified on Tuesday, July 23, 2019 9:27 AM