Arnica is a traditional homeopathic remedy that’s commonly used for bruising and to help treat injuries. Little medical research has evaluated arnica’s safety and efficacy for treating bruises, so you must consult your doctor before using arnica. You should also seek a licensed professional homeopath to administer arnica remedies.
Benefits
Arnica may help treat bruises and contusions from traumatic injuries caused by blunt objects, according to the University of Michigan Health System. Arnica may also help relieve soreness and bleeding from surgery, dental work, sprains, strains and physical exertion. Arnica is commonly recommended for promoting wound healing and as a treatment for minor injuries.
Application
Arnica can be used both internally and topically to treat bruises. To apply topically, mix 1 tbsp. of arnica tincture in about 17 oz. of water, and then soak a cloth in the solution, explains the University of Michigan Health System. Apply the cloth to the bruised skin area for about 15 minutes, four to five times each day. For internal use, follow the instructions of a professional homeopath regarding proper dosage. The U.S. Food and Drug Administration has deemed arnica an unsafe herb for internal use because it has caused negative effects on the uterus, lungs and hearts of some users, notes the Memorial Sloan-Kettering Cancer Center. Before using arnica, talk with your doctor about the proper dosage and application.
Function
Arnica appears to provide antimicrobial and anti-inflammatory actions that might account for its benefits in treating wounds and bruises. It contains terpenoids including sesquiterpenes and helenalin. Helenalin in particular seems to provide the anti-inflammatory effects on bruised skin, explains the Memorial Sloan-Kettering Cancer Center.
Scientific Evidence
A pilot clinical trial published in the "British Homeopathic Journal" in 1976 found that taking arnica before and after bruising due to an injury helped to relieve the pain and decrease the size of the bruise, according to the University of Pittsburgh Medical Center. Few other studies were able to find any benefit of oral or topical arnica in treating bruises, however.
Warnings
You might experience contact dermatitis, burning or itching when you apply arnica topical remedies to your skin, but these side effects are relatively rare. Ingesting arnica in oral remedies might cause gastrointestinal distress, difficulty breathing, heart problems, coma and even death. The FDA’s Poisonous Plant Database cites one case where ingesting 70 g of arnica tincture caused a poisoning death, notes the Memorial Sloan-Kettering Cancer Center. Taking arnica internally could also reduce the effects of medications that treat hypertension, and increase the effects of blood-thinners like anticoagulant and antiplatelet medications, such as Coumadin.
