Yellow Bark

A genus of 125 species of deciduous and evergreen, often thorny trees and shrubs that occur mainly in northern temperate regions. Rhamnus frangula and R. cathartica are ideal for hedges in a wild or woodland garden. The former, which grows wild in damp, peaty ground, has good autumn color, and its flowers are especially attractive to bees. It was once grown to make charcoal for small-arms gunpowder. Rhamnus purshiana, which is native to coastal redwood and mixed evergreen forests, is particularly noticeable in winter, forming groups of upright, silver-gray stems. The bark of Rhamnus species contains anthraquinone glycosides, which have strong purgative effect and cause severe griping pains, nausea, and vomiting unless stored for at least a year after drying. Rhamnus cathartica has been used as a purgative since at least the 9th century and was included in the British Phamacopoeia in 1650. Its effect is so drastic that it is no longer prescirbed, although buckthorn syrup, made from the berries, is used in veterinary practice. Rhamnus frangula and R. purshiana have superseded R. cathartica in medicine, having a gentler effect; the latter is mild enough for treating children and the elderly. Rhamnus purshiana was first listed in the U.S. Pharmacopoeia in 1890. Indiscriminate stripping of bark, leading to the destruction or some 100,000 trees a year, was reported as early as 1909, and shortages led to the exploitation of the much smaller R. alnifolia (alder buckthorn), which is similar in chemistry. Anthraquinones are pigments, so plants that contain them are almost always used for dyeing — a purpose that usually predates their importance in medicine. Rhamnus infectoria (Avignon berry) was one an important source of yellow dye; R. davurica and R. utilis were sources of the pigment known as "Chinese green indigo", used in dyeing silk. Fruits of R. cathartica, known as "Rhine berries", also yield an artist's pigment.

Cascara sagrada, which means "sacred bark", got its name from seventeenth-century Spanish missionaries who noticed its excellent effects on constipation and upset stomach among Native Americans. One of the safest natural laxatives available, cascara sagrada helps restore tone to the colon and overcome laxative dependence in the elderly.

Lax, evergreen shrub or tree with obovate, irregularly toothed, deeply veined leaves, to 15cm (6in) long. Umbels of small flowers appear in late spring, followed by poisonous black berries, 1cm (½in) in diameter.

Common Name:	Yellow Bark
Other Names:	Bitter Bark, California Buckthorn, Cascara, Cascara Sagrada, Chittem bark, Dogwood, Sacred Bark, Sagrada bark, Wahoo
Botanical Name:	Rhamnus purshianus
Genus:	Rhamnus
Family:	Rhamnaceae
Native Location:	Western N America
Cultivation:	Well-drained soil in sun or partial shade. Rhamnus cathartica prefers alkaline soil, R. frangula neutral to acid soil. Shorten of thin out branches, and remove dead wood, in late winter or early spring.
Propagation:	By seed sown when ripe; by greenwood cuttings in early summer; by layering in autumn or early spring.
Harvest:	Bark is stripped from young plants during spring and early summer, and it is dried for one to two years before being used in decoctions, liquid extracts, powders, and tablets. Bark from two-year-old plants is preferred in the case of R. frangula. Fruits (R. cathartica) are collected when ripe and they are made into syrup.
Height:	3-12m (10-40ft)
Width:	3-10m (10-30ft)
Hardiness:	Z7
History:	A native of the Pacific Northwest, cascara sagrada—Spanish for "sacred bark"—received its name from Spanish missionaries who settled in California during the 1600s. The same missionaries probably started the myth that the branches of cascara sagrada were used to make Christ's crown of thorns almost 2,000 years before. Not very likely for a genus that thrives mainly in northern temperate climates. The Native Americans of the Northwest has a more pragmatic view of this smallest of the buckhorn trees: They used its bark to treat constipation. And famously so. By the early 1800s, cascara sagrada had gained a national reputation among American settlers as one of the fastest-acting but safest of laxatives. By the late 1800s, that giant of pharmaceutical companies Parke-Davis was producing and marketing cascara sagrada commercially.
Parts Used:	Bark
Properties:	A bitter, astringent, cooling herb that has a tonic effect on the liver and digestive system, and acts as a laxative.
Medicinal Uses:	Internally for chronic constipation, colitis, digestive complaints, hemorrhoids, liver problems, and jaundice. Externally for nailbiting. To treat hemorrhoids, constipation, rheumatism, and poor digestion; as a tonic; for cleaning wounds. Germany's Commission E has approved the use of cascara sagrada to treat constipation. Cascara sagrada has astringent, laxative, and tonic properties. It also helps normalize the digestive tract and the liver, and is rich in calcium, potassium, manganese, and vitamins A, B2, and B5. Cascara sagrada is taken internally as a stomach and liver tonic to treat colic, constipation, hemorrhoids, indigestion, jaundice, and liver ailments. Veterinarians use cascara sagrada to treat chronic constipation in dogs.
Preparation:	Cascara sagrada is available as dried, powdered bark, and in capsules, teas, and tinctures. To make a tea, pour 1 cup of boiling water over 1 teaspoon of dried bark and steep for 1 hour. Drink up to 2 cups a day before meals.
Typical Dose:	A typical dose of cascara sagrada may range from 20 to 30 mg of the active ingredient (hydroxyanthracene derivatives)
Caution:	Although many herbalists claim that cascara sagrada is mild enough to be taken safely by young children and pregnant women, we strongly recommend consulting a qualified practitioner about giving the herb to children or taking it if you are pregnant. Special note: The fresh bark of cascara sagrada is never used medicinally; it can cause severe intestinal cramping and nausea. Herbalists only use bark that has been aged for at least one year.
Possible Side Effects:	Cascara sagrada's side effects include abdominal discomfort, colic, and cramps.
Drug Interactions:	Digoxin Taking cascara sagrada with these drugs may reduce the absorption of the drug: All oral Medications Ferric Gluconate, (Ferrlecit) Ferrous Fumarate, (Fermiron, Feostat) Ferrous Gluconate, (Fergon, Novo-Ferrogluc) Ferrous Sulfate, (Feratab, Fer-Iron) Ferrous Sulfate and Ascorbic Acid, (Fero-Grad 500, Vitelle Irospan) Iron-Dextran Complex, (Dexferrum, INFeD) Polysaccharide-Iron Complex, (Hytinic, Niferex) Taking cascara sagrada with these drugs may increase the risk of arrhythmia (irregular heartbeat): Acebutolol, (Novo-Acebutolol, Sectral) Adenosine, (Adenocard, Adenoscan) Amiodarone, (Cordarone, Pacerone) Bepridil, (Vascor) Bretylium, (Bretylium) Digitalis, (Digitek, Lanoxin) Diltiazem, (Cardizem, Tiazac) Disopyramide, (Norpace, Rhythmodan) Dofetilide, (Tikosyn) Esmolol, (Brevibloc) Flecainide, (Tambocor) Ibutilide, (Corvert) Insulin, (Humulin, Novolin R) Lidocaine, (Licoderm, Xylocaine) Mexiletine, (Mexitil, Novo-Mexiletine) Moricizine, (Ethmozine) Phenytoin, (Dilantin, Phenytek) Procainamide, (Procanbid, Pronestyl-SR) Propafenone, (Gen-Propafenone, Rhythmol) Propranolol, (Inderal, InnoPran XL) Quinidine, (Novo-Quinidin, Quinaglute Dura-Tabs) Sildenafil, (Viagra) Sotalol, (Betapace, Sorine) Tocainide, (Tonocard) Verapamil, (Calan, Isoptin SR) Taking cascara sagrada with these drugs may increase the risk of hypokalemia (low levels of potassium in the blood): Acetazolamide, (Apo-Acetazolamide, Diamox Sequels) Azosemide, (Diat) Beclomethasone, (Beconase, Vanceril) Betamethasone, (Celestone, Diprolene) Budesonide, (Entocort, Rhinocort) Budesonide and Formoterol, (Symbicort) Bumetanide, (Bumex, Burinex) Chlorothiazide, (Diuril) Chlorthalidone, (Apo-Chlorthalidone, Thalitone) Cortisone, (Cortone) Deflazacort, (Calcort, Dezacor) Dexamethasone, (Decadron, Dexasone) Digitalis, (Digitek, Lanoxin) Ethacrynic Acid, (Edecrin) Etozolin, (Elkapin) Flunisolide, (AeroBid, Nasarel) Fluorometholone, (Eflone, Flarex) Fluticasone, (Cutivate, Flonase) Furosemide, (Apo-Furosemide, Lasix) Hydrochlorothiazide, (Apo-Hydro, Microzide) Hydrocortisone, (Cetacort, Locoid) Hydroflumethiazide, (Diucardin, Saluron) Indapamide, (Lozol, Nu-Indapamide) Loteprednole, (Alrex, Lotemax) Mannitol, (Osmitrol, Resectisol) Medrysone, (HMS Liquifilm) Mefruside, (Baycaron) Methazolamide, (Apo-Methazolamide, Neptazane) Methyclothiazide, (Aquatensen, Enduron) Methylprednisolone, (Depo-Medrol, Medrol) Metolazone, (Mykrox, Zaroxolyn) Olmesartan and Hydrochlorothiazide, (Benicar HCT) Polythiazide, (Renese) Prednisolone, (Inflamase Forte, Pred Forte) Prednisone, (Apo-Prednisone, Deltasone) Rimexolone, (Vexol) Torsemide, (Demadex) Triamcinolone, (Aristocort, Trinasal) Trichlormethiazide, (Metatensin, Naqua) Urea, (Amino-Cerv, Ultramide) Xipamide, (Diurexan, Lumitens) Taking cascara sagrada with these drugs may increase the loss of electolytes and fluids: Docusate amd Senna, (Peri-Colace, Senokot-S) Taking cascara sagrada with these drugs may be harmful: Indomethacin, (Indocin, Novo-Methacin) May interfere with the action of the drug.
Lab Test Alterations:	Increased or decreased test values of serum and 24-hour urine estrogens. May confound results of diagnostic urine tests that rely on color change by discoloring urine. May decrease serum potassium concentrations and cause potassium depletion
Disease Interactions:	May worsen Crohn's disease, ulcerative colitis, and other gastrointestinal diseases.
Food Interaction:	Decreased action of cascara sagrada when taken with milk
Supplement Interactions:	Increased risk of hypokalemia (low levels of potassium in the blood when used with potassium-depleting herbs, such as Horsetail Plant, Licorice Root, and Strophanthus. Increased action of Jimson Weed in cases of chronic use of cascara sagrada. Increased risk of cardiotoxicity from potassium-depletion especially when cascara sagrada is overused or taken with cardioactive herbs, such as Adonis, Digitalis, Lily-Of-The-Valley, and Squill. Increased risk of potassium depletion when used in conjunction with Horsetail Plant, or Licorice. Increased risk of potassium depletion when used with other stimulant laxative herbs, such as Blackroot, Castor Oil, and Senna.
Warning:	All parts, especially the berries are harmful if eaten. Sap and berries are skin irritants. Fruits taken in excess cause diarrhea and vomiting. Contraindicated during pregnancy and lactation, and for intestinal obstruction.
Economic Uses:	Bark extracts, with bitterness removed, are used for flavoring in the food and soft drink industries.
Bibliography:	Encylopedia of Herbs by Deni Brown Copyright ©: 1995, 2001 Dorling Kindersley Limited pp 342-343 The Essential Herb-Drug-Vitamin Interaction Guide by Geo. T. Grossberg,MD and Barry Fox,PhD Copyright©2007 Barry Fox,PhD. Pp.125-128 The Modern Herbal Primer by Nancy Burke Copyright©2000 Yankee Publishing, Inc. pg 134.