Turnera diffusa (Willd.)
Synonyms: var. T. aphrodisiaca (Urb.), Turnera, Mexican damiana
Order: Turneraceae
Description: Turnera is a shrub which grows up to 2m high, with many-branched smooth, straight yellow or reddish-brown stems. The small leaves are alternate or in bunches and have toothed margins; their upper surface is pale green, the underside covered with pale hairs. They have a strong aroma reminiscent of chamomile. Small yellow flowers grow in the leaf axils. The fruits are small capsules, tripartite and slightly curved. It is native to Texas, Mexico and Central America and prefers hot, humid climates.
Parts used: leaves and stems
Collection: The leaves and stems are gathered during the flowering period.
Constituents: Up to 1% volatile oil (including alpha and beta pinene, cineole, arbutin, thymol, cymene, alpha copaene, beta cadinene, calamenene, beta sitasterol), alkaloids, a cyanogenic glycoside, the hydroquinone arbutin, a bitter amorphous substance (damianin), flavonoids, tannins, resins, gum
Actions: stimulant, mild diuretic, mild laxative, antidepressant, thymoleptic, urinary antiseptic, mild purgative, reputed aphrodisiac, testosteromimetic, euphoric and nervous restorative, stomachic
Indications: Depression, nervous dyspepsia, atonic constipation, coital inadequacy, debility, lethargy. Specifically indicated in anxiety neurosis with a predominant sexual factor.
Therapeutics and Pharmacology: Turnera is a valuable strengthening remedy for the nervous system. In particular, it has a stimulating and enhancing action on those functions related to the male reproductive system, especially where there is sexual inadequacy with a strong psychological or emotional element. The alkaloids are thought to have a testosteronal effect. It is of benefit in any debilitated condition of the central nervous system from anxiety and depression to neuralgia; and is used to contain genital herpes. Although considered to be a 'male' herb, it is not contraindicated for women with debilitated conditions.
Combinations: Turnera combines well with Avena, Cola, Scutellaria and/or Humulus in nerve diseases.
Caution: Excessive doses may cause insomnia and headache.
Preparation and Dosage: (thrice daily)
Regulatory Status: GSL Schedule 1
Dried leaves: 2-4g or by infusion
Liquid Extract (B.P.C. 1934): 1:1 in 60% alcohol, 3-6ml
Additional Comments: In Chinese medicine Damiana is used to 'warm' the kidneys.
Bibliography
Bradley, P.R. (ed.) 1992 British Herbal Compendium, Volume 1, BHMA, Bournemouth.
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 Essential Book of Herbal Medicine, Penguin, London (First published in 1991 as Out of the Earth, Arkana)
Mills, S.Y. 1993 The A-Z of Modern Herbalism, Diamond Books, London.
Ody, P. 1993 The Herb Society's Complete Medicinal Herbal, Dorling Kindersley, London.
Wren, R.C. 1988 Potter's New Cyclopaedia of Botanical Drugs and Preparations, C.W.Daniel, Saffron Walden.
