Thuja occidentalis (L)
Synonyms: Arbor vitae, tree of life, white cedar, yellow cedar, American cedar, hackmatack
Order: Cupressaceae
Description: Thuja is an evergreen conifer, which can reach a height of 20m in its native habitat. It is indigenous to North America, forming dense forests. It prefers wet soil, and is grown in European gardens and parks. The branches are short, the lower ones horizontal, the upper ones crowded and forming a dense, conical head. The opposite pairs of bright green, acute leaves resemble overlapping scales, and have an aromatic odour when crushed. The minute, solitary terminal flowers appear from April to July and are yellow or greenish in colour. The small cone is pale green when young, light reddish-brown with pointless, thin, oblong scales when old.
Parts used: young twigs and leaves
Collection: The twigs are at their best in summer
Constituents: 1% volatile oil (including up to 65% thujone, also fenchone, borneol, limonene, pinene, camphor and myrcene), flavonoid glycoside (thujin), mucilage, tannin
Actions: nerve stimulant, expectorant, stimulant to smooth muscles, particularly the bronchial muscle and the genito-urinary system and vasculature; emmenagogue, antiseptic, anti-inflammatory, diuretic, astringent, counter-irritant, stimulating alterative, vermifuge
Indications: bronchial catarrh, enuresis, cystitis, psoriasis, amenorrhoea, rheumatism
Therapeutics and Pharmacology: Thuja's main action is due to its stimulating volatile oil. In bronchial catarrh it combines an expectorant action with systemic stimulation. It is a smooth muscle stimulant with a specific reflex action on the uterus and thus may help in delayed menstruation. It is of use in cases of enuresis and cystitis. It may also be used where loss of muscle tone causes urinary incontinence. Thuja has a role to play in the treatment of psoriasis and rheumatism; a hot compress eases rheumatic pains. Externally it may be used to treat warts, genital and anal warts in particular; the tincture should be applied twice a day for several weeks. A marked antifungal effect is found if used externally for ringworm and thrush. An infusion may also be applied externally to scabies and impetigo. Thuja counteracts the side-effects of smallpox vaccination, and has been used as a constituent of a herbal regime for the treatment of carcinomas of the chest and breasts.
Combinations: When used in pulmonary conditions it may be combined with Lobelia. It may also be added to Hamamelis water as a lotion for exudative eczema.
Caution: Thuja should be avoided when a cough is due to overstimulation, as in dry, irritable coughs. It should not be taken during pregnancy due to its stimulant effect on the uterus. Thujone, the main constituent of the volatile oil, is toxic in any quantity, and deaths have been recorded, so the herb should only be taken internally under medical supervision, in small doses, and for no more than a week or two at a time.
Preparation and Dosage: (thrice daily)
Dried herb: 1-2g or by infusion
Liquid Extract: 1:1 in 50% alcohol, 2ml
Tincture: 1:10 in 60% alcohol, 1-2ml
Additional Comments: Thuja was a Native American remedy for delayed menstruation, headache and heart pain, and was also used to reduce swelling.
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.
Ody, P. 1993 The Herb Society's Complete Medicinal Herbal, Dorling Kindersley, London.
