Arnica usually refers to
Arnica Monatan, a mountain plant used for relief of bruises, stiffness, aftereffects of falls, blows sports injuries, overexertion and muscle soreness. It makes black & blue marks go away faster & relieves the pain, swelling & stiffness caused by physical trauma. It is a favorite of athletes, coaches & trainers. Immediately after over-exercising or recovering a minor injury, apply Arnica Gel to ward off pain, stiffness & black-&-blue marks. Arnica is widely used as a salve for bruises and sprains, and sometimes as a tincture, for the same anti-inflammatory, pain-relieving purposes.