Since I do martial arts and my girlfriend Lelak does CrossFit, we both manage to get a large number of bruises between the two of us. Therefore a very common question heard in our household is “have you put arnica on that?”. Coming home from training last night sporting some lovely new bruises made me wonder if arnica really does make bruises heal faster than doing nothing at all and if any scientific studies have been done on the effectiveness of arnica.
Arnica is a genus with about 30 perennial, herbaceous species, belonging to the sunflower family, Asteraceae. Within this genus, several species, such as Arnica montana and Arnica chamissonis, contain helenalin, which is a a major ingredient in anti-inflammatory preparations, mostly used to treat bruises.
A bruise is caused by the capillaries bursting open and blood spilling into the surrounding tissue. As your body attempts to heal itself, it sends white blood cells to the area to clean up the spilt blood. Arnica is said to increase the number of white cells sent to the area causing the blood to be cleaned up faster and your bruise to fade quicker. But does this actually occur?
Scouring PubMed for studies into the effectiveness of arnica, I could find only one that related to arnica’s effectiveness in treating bruising. This was a study from August 2002 in Dermatologic Surgery titled Effects of topical arnica gel on post-laser treatment bruises by Alonso, Lazarus & Baumann. In this study the authors had 19 patients in a randomized, double-blinded, placebo-controlled study where half the patients applied a cream containing arnica to one side of their face and another cream containing no active ingredient to the other side for two weeks before laser treatment. The other half of the group did the same thing but for two weeks after laser treatment. The results- no difference whatsoever in the prevention or healing of the bruising on the side of the face treated with the arnica compared to the side of the face without it.
However, just one study with a small number of patients doesn’t prove conclusively that arnica isn’t effective, so I went looking for more evidence, this time on Medline Plus. In their article on the first aid treatment for bruises from the Mayo Clinic, it doesn’t mention using Arnica at all. Instead, they recommend that you apply ice to the area several times a day for the first 2 days and use Tylenol or Ibuprofen for pain relief. The only sites I could find promoting the use of Arnica were natural therapy sites which contained no references to any studies done proving that Arnica is effective in healing bruises faster than if you did nothing at all.
Based on my research, I am not convinced that Arnica decreases the healing time of bruises. In my opinion what probably does decrease the healing time is actually rubbing the bruised area. This would increase blood flow to the area thus bringing more white cells to the area to assist in cleaning up the blood and reducing how long it takes for the bruise to fade. Arnica has nothing to do with it at all.