Arnica montana, also known as wolf's bane, leopard's bane, mountain tobacco and mountain arnica, is a moderately toxic ethnobotanical European flowering plant in the sunflower family. It is noted for its large yellow flower head.
Description: Arnica montana is used as an herbal medicine for analgesic and anti-inflammatory purposes. Clinical trials have produced mixed results.
Usage: Historically, Arnica montana has been used as an herbal medicine for centuries. Traditional uses for the plant are similar to those for willow bark, with it generally being employed for analgesic and anti-inflammatory purposes. Clinical trials of Arnica montana have yielded mixed results: When used topically in a gel at 50% concentration, A. montana was found to have the same effectiveness (but with maybe worse side effects) as a 5% ibuprofen gel for treating the symptoms of hand osteoarthritis. A. montana has also been the subject of studies of homeopathic preparations. A 1998 systematic review of homeopathic A. montana conducted at the University of Exeter found that there are no rigorous clinical trials that support the claim that it is efficacious beyond a placebo effect. Toxicity The US Food and Drug Administration has classified Arnica montana as an unsafe herb because of its toxicity. It should not be taken orally or applied to broken skin where absorption can occur. Arnica montana contains the toxin helenalin, which can be poisonous if large amounts of the plant are eaten or small amounts of concentrated Arnica are used. Consumption of A. montana can produce severe gastroenteritis, internal bleeding of the digestive tract, raised liver enzymes (which can indicate inflammation of the liver), nervousness, accelerated heart rate, muscular weakness, and death if enough is ingested. Contact with the plant can also cause skin irritation. In the Ames test, an extract of A. montana was found to be mutagenic.