What is Arnica?

Arnica Fact #1

From the mountainous regions of Central Europe, Arnica montana is recognized for its medicinal properties. It uses its ingenious properties to protect itself from its environment.

How to recognize Arnica

With its hairy stem and its large yellow‑orange flower, Arnica montana is an easily identifiable wild plant.

A vibrant plant that grows to be 20 to 60 cm tall, Arnica montana is most often recognized by its yellow-orange capitula (flowers). Arranged in a daisy shape, the flower is relatively large (6‑8 cm).It usually blooms alone (or in groups of three or four) and gives off a strong odor. Like many Asteraceae, the capitula is composed of female ligulated flowers and hermaphrodite tubulated flowers.

Arnica can also be distinguished by its pale green stem, which is covered in strong‑smelling glandular hairs (trichomes). In addition, it can be distinguished by the flowers found at its base, which are oval‑shaped and have longitudinal ribs that stand out on its underside; this is called the rosette.

Another characteristic is its 20 to 50 cm flowering stem, which often holds two small opposite or sub‑opposite caulinary leaves.

Finally, Arnica leaves are relatively thick and hairy. These hairs have two advantages for the plant:

• by reflecting light, they protect it from burns, evaporation and drying,
• and by sticking up in a bristly manner, they ward off the sensitive mouths of animals, such as cows, goats and sheep.

The fruit is an achene (dry fruit) topped with a feathery crest, the seed of which is slightly hairy.

Arnica has an important underground network. Its underground stem, called the rhizome, is used for reproduction. It is also pollinated by insects, and its seeds are scattered by the wind.

Related to Chamomile

There are approximately 30 species of Arnica, and these perennial, herbaceous plants belong to the Asteraceae family, as do chamomile and marigolds.

The most used species are as follows: Arnica montana and Arnica chamissonis, which are present in Europe, as well as Arnica fulgens, Arnica sororia and Arnica cordifolia, which come from North America.

Popular Names for Arnica

• In French, “herb for falls:” This name refers to its traditional use for centuries in the treatment of pain related to an impact (bruise or bump) or muscle fatigue (cramps or aches).
• In French, “herb for sneezes:” The word “arnica” is a deformation of the Greek word “ptarnica,” which means “which makes one sneeze.”
• In French, Vosges tobacco or Savoy tobacco; in English, mountain tobacco: An allusion to the ancient uses of arnica leaves.

Arnica Fact #2

Getting to know Arnica

Arnica montana contains many chemical compounds. The quality of the plant particularly depends on the presence of a certain number of active substances, the content of which varies naturally.

The substances that Arnica produces generally help it protect itself. Its composition, therefore, strongly depends on its surrounding1 underground and air environment (animals, insects, sun, pH of the soil, etc.).

For Example

• Sesquiterpene lactones with anti-inflammatory properties described in the European Pharmacopoeia are found in the hairs of the bracts1, capitula in bloom and leaves.
  Their bitter taste is used to protect the plant from herbivore animals1.
• Flavonoids, widely represented in the phlebotonic2 and anti-inflammatory class of medicines, are a family of compounds that can also be found in the stems and leaves of Arnica Montana1.
  Their antioxidant activity makes it possible for the plant to protect itself from the damaging effects of sunlight3,4
• Essential oils (mainly thymol used pharmaceutically for its antiseptic properties5) can be found in the capitula and the leaves, but are found mainly in the rhizomes and roots.
  They protect the plant from bacteria and fungi contained in the soil.

Did You Know?

Arnica has been known since the twelfth century, and the description of Arnica written by the abbess Hildegarde of Bingen (Saint Hildegarde) is used in the traditional Pharmacopoeia.

Arnica Fact #3

Conditions for the development of Arnica

Arnica montana is a “diva;” its requirements in terms of altitude, soil and climate mean it doesn’t grow just anywhere.

Arnica montana, or mountain arnica, likes acidic, siliceous, non-calcareous soil (pH between 5 and 5.5). It also needs land with a slope of at least 3°, which prevents stagnant moisture (which is too humidifying) and ensures satisfactory water circulation. “Arnica is a diva because it needs water, but not too much,” explains Françoise Merceron, pharmacist and head of plant purchasing for Laboratoires Boiron.

Sensitive to sudden and significant temperature variations, Arnica montana grows in high-altitude meadows (at more than 800 m) in the mountainous regions of Central Europe, from southern Sweden to northern Spain.

In France, it is mainly found:

• in the East, inVosges (where the granitic soil is particularly favourable to Arnica), in the Alps, and, much more rarely, in Jura;
• in the Centre, in Morvan, Central Plateau and Cevennes;
• and in the Southwest, in the Central Pyrenees.

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1 Botanique, biologie et physiologie végétales [Botany, biology and vegetal physiology] 2nd revised edition Maloine
2 Vidal 2014
3 Observatoire National des effets sur le réchauffement climatique, [National Observatory on the effects of global warming], Technical Note No. 3 January 2006
4 Kouzi, Am J Health-Syst Pharm—Vol 64 Dec 1, 2007 p 2434-2442
5 Dorland’s Illustrated Medical Dictionary, 28th ed.