Image source: https://upload.wikimedia.org/wikipedia/commons/1/17/Arnica_montana_-_Köhler–s_Medizinal-Pflanzen-015.jpg
Common name Arnica
Plant family Compositae/Asteraceae
Parts used Flower
Qualities Cool, neutral (Holmes, 2007).
Constituents Sesquiterpene lactones- pseudoguaianolide type (0.2% to 1.5%), including helenalin and 11alpha, 13-dihydrohelenalin and their ester derivatives; triterpenes, including arnidiol; flavonoids (0.4% to 0.6%) including quercitin; 3-O-glucuronic acid; lignans including pinoresinol; coumarins, carotenoids; non-toxic pyrrolizidine alkaloids (tussilagine and isotussilagine);
polyacetylenes; essential oil (0.23% to 0.35%) containing sesquiterpenes; thymol derivatives and other monoterpenes; caffeoylquinic acids (phenolic acids) including 3,5- and 1,5-dicaffeoylquinic acids (Bone & Mills, 2013).
Actions
TOPICAL ONLY, anti-inflammatory, anti-ecchymotic, analgesic, anti-microbial (Bone, 2003). Antiphlogistic (Gruenwald, Brendler & Jaenicke, 1998).
Indications Per Grieve, arnica montana is suitable for "external application to sprains, bruises, and wounds, and as a paint for chilblains when the skin is unbroken", and will make hair grow back if it is applied to the scalp (Grieve, 1971).
Bone and Mills also recommend topical A. montana for hair loss as in alopecia neurotica, also to prevent dandruff and to stimulate circulation in the scalp (Bone & Mills, 2013).
Per Bone, suitable for chronic venous insufficiency, particularly where lower limbs feel heavy and oedema is present; muscle ache; bruises, sprains; inflamed insect bites; haematomas, dislocations, oedema resulting from fracture; rheumatic muscle and joint problems, superficial phlebitis; furunculosis; painful swellings, unbroken chilblains; alopecia neurotic (Bone, 2003).
Physician's Desk reference advises that A. montana has a fever-relieving effect when applied topically.
A clinical trial of a commercially available arnica gel ("Atrogel") preparation at a concentration of 500 mg arnica extract per 1g of gel found that it reduced pain and stiffness associated with osteoarthritis of the knee, and to ameliorate restriction-of-function (Knuesel, Weber & Suter, 2002). Further study with the same preparation found that it was as effective as ibuprofen for relieving pain and improving function in patients with arthritis in the hands (Widrig, Suter, Saller & Melzer, 2007).
Cautions Not for prolonged treatment, as may cause oedematous dermatitis and pustules, and may provoke eczema (European Scientific Cooperative on Phytotherapy, 2003). Not to be taken internally and apply only to UNBROKEN skin (Bone, 2003). Hoffman advises that topical applications can cause allergy and inflammation in some patients (Hoffmann, 2003). The "Final report on the safety assessment of Arnica montana extract and Arnica montana" by the International Journal of toxicology found evidence that A. montana may be mutagenic; therefore might be cautioned in pregnancy ('Final Report on the Safety Assessment of Arnica Montana Extract and Arnica Montana', 2001). A number of other publications including Bone do not specifically caution against its use in pregnancy and lactation, beyond reiterating that it is for external use only (Bone, 2003).
Contraindications
Not to be used internally.
Dosage Lotion: dilute a 1:5 tincture five times with water. Apply two to three times per day. Ointments made should contain 10-25% tincture and be applied 2-3 times daily (Bone & Mills, 2013).
Combinations Grieve advises arnica flowers may be adulterated with other Compositae flowers such as Calendula officinalis, Inula brittanica, Kragapogon pratensis, and Scorzonera humilis (Grieve, 1971).
References
Bone, K. (2003). A clinical guide to blending liquid herbs. Edinburgh [u.a.]: Churchill Livingstone.
Bone, K., & Mills, S. (2013). Principles and practice of phytotherapy. Edinburgh: Churchill Livingstone.
European Scientific Cooperative on Phytotherapy,. (2003). ESCOP monographs : the scientific foundation for herbal medicinal products (2nd ed.). Exeter: Thieme.
Final Report on the Safety Assessment of Arnica Montana Extract and Arnica Montana. (2001). International Journal Of Toxicology, 20(2), 1-11.
Grieve, M. (1971). A modern herbal. New York: Dover Publications.
Gruenwald, J., Brendler, T., & Jaenicke, C. (1998). PDR for herbal medicines. Montvale, New Jersey: Medical Economics.
Hoffmann, D. (2003). Medical herbalism. Rochester, Vt.: Healing Arts Press.
Holmes, P. (2007). The energetics of Western herbs. Cotati, Calif.: Snow Lotus Press.
Knuesel, O., Weber, M., & Suter, A. (2002). Arnica montana gel in osteoarthritis of the knee: An open, multicenter clinical trial. Adv Therapy, 19(5), 209-218.
Widrig, R., Suter, A., Saller, R., & Melzer, J. (2007). Choosing between NSAID and arnica for topical treatment of hand osteoarthritis in a randomised, double-blind study. Rheumatol Int, 27(6), 585-591.