Arnica cream or gel is used topically to heal wounds and rashes, treat acne and boils, soothe sore muscles, calm inflammation and decrease swelling, according to WebMD. Arnica relieves pain and promotes blood reabsorption. Arnica is helpful in treating bruises, adds Healthline.
Topical arnica is commonly used to reduce pain and bruising and speed healing by individuals who have undergone plastic surgery, reports Healthline. Studies show that arnica gel is effective in treating knee osteoarthritis, but another study found it to be only as effective as ibuprofen for reducing the pain of hand arthritis. In another study on leg pain, arnica increased calf pain after 24 hours, so the efficacy results for arnica are mixed as of 2015.
The Arnica Montana is a yellow-orange flower found in Europe and Siberia, derived from the same family as daisies, dandelions, marigolds and sunflowers, notes WebMD. Arnica is for topical use only; the flower is toxic if ingested and can cause vomiting, interfere with breathing, and result in a heart attack or death. Individuals may develop a skin rash due to an allergic reaction to arnica, especially if hypersensitivity exists to other members of the same flower family. Arnica should not be used on wounds or broken skin. Pregnant and nursing women should not use arnica; the Food and Drug Administration does not regulate the homeopathic product.