Zanthoxylum americanum (Mill.)
Synonyms: X, toothache bush, toothache tree, toothbrush bush, yellow wood, suterberry, northern prickly ash (southern prickly ash is Zanthoxylum L).
Order: Rutaceae
Description: Zanthoxylum is a native North American shrub or tree, growing form 3-8m tall and inhabiting damp soils from Canada to Virginia and Nebraska. The branchlets bear prickles up to 1.5cm long. The leaves are alternate and odd-pinnate, with 5-11 ovate or elliptic leaflets that are softly hairy beneath. Small, yellowish-green flowers grow in axillary clusters during April and May, before the leaves appear. The fruit is a small, berry-like capsule captaining one or more shiny black seeds.
Parts used: bark and berries
Collection: the berries are collected in late summer and the bark is stripped in the spring.
Constituents: The bark contains alkaloids (including chelerythrine, magnoflorine, nitidine and lauroflorine), pyranocoumarins (only in Z.americanum) including zanthyletin and zanthoxyletin; resin, tannin, acrid volatile oil
Actions: circulatory stimulant, tonic, alterative, carminative, diaphoretic, antirheumatic, sialogogue, anodyne, irritant, antipyretic, antidiarrhoeal, emmenagogue. The berries are carminative, aperient and antispasmodic.
Indications: peripheral circulatory insufficiency and chronic rheumatic conditions (berries more so than bark).
Therapeutics and Pharmacology: Zanthoxylum may be used in the same way as Capsicum as a circulatory stimulant, although it is slower in action. It may be used where there is poor circulation, for example, chilblains, leg cramps, varicose veins and varicose ulcers. It is indicated in intermittent claudication and Raynaud's syndrome. Zanthoxylum stimulates the salivary glands and mucous membranes, reduces colic and flatulence, and is strengthening to a debilitated digestion. It is used in the treatment of chronic skin diseases and is locally counter-irritant. A liniment may be used to treat rheumatism and fibrositis. The bark was chewed in the past to relieve toothache. The berries are often used for dyspepsia and indigestion.
Combinations: Zanthoxylum may be combined with Myrica and Zingiber in poor circulation; and with Guaiacum , Menyanthes and Capsicum in rheumatic conditions.
Caution: The isolated benzophenanthridene alkaloids are reported to be destructive to cells. There are, however, no accounts of adverse side-effects from taking this herb in therapeutic doses.
Preparation and Dosage:
Regulatory Status: GSL
Decoction: Pour a cup of water onto 1-2 teaspoons of bark and simmer for 10-15 minutes. Drink three times a day.
Liquid extract: 1:1 in 45% alcohol, 1-3ml three times a day.
Tincture: 1:5 in 45% alcohol, 2-5ml three times a day.
Additional Comments: Prickly ash bark was a toothache remedy for the Native Americans, who also boiled the inner bark to make a wash for itching skin. It was brought to Europe in the mid-19th century for the same purpose.
Bibliography
BHMA 1983 British Herbal Pharmacopoeia, BHMA, Bournemouth.
Grieve, M. 1931 A Modern Herbal, (ed. C.F. Leyel 1985), London.
Hoffmann, D. 1990 The New Holistic Herbal, Second Edition, Element, Shaftesbury.
Lust, J. 1990 The Herb Book, Bantam, London.
Mabey, R. (ed.) 1991 The Complete New Herbal, Penguin, London.
Mills, S.Y. 1993 The A-Z of Modern Herbalism, Diamond Books, London.
Polunin, M. and Robbins, C. 1992 The Natural Pharmacy, Dorling Kindersley, London.
Wren, R.C. 1988 Potter's New Cyclopaedia of Botanical Drugs and Preparations, C.W.Daniel, Saffron Walden.
