I recently received an e-mail from a reader who inquired about the scientific evidence surrounding a popular homeopathic remedy known as Arnica montana. In order to answer this inquiry, I first need to address the issue of homeopathy in general. Homeopathy is a controversial holistic treatment that centers around the theory that “like cures like” – an admittedly unconventional view. Homeopathic remedies are also fodder for vigorous debate in the scientific community because they contain extremely diluted amounts of medicinal elements. In essence, the underpinning theory is that the lower the dosage, the more potent the effect. This claim goes against the generally accepted laws of chemistry and physics. Nevertheless, many consumers and select physicians are stalwart supporters of this esoteric practice.

In the interest of full disclosure, I need to admit that I have a difficult time accepting the principles espoused by proponents of homeopathy. At the same time, I’m willing to follow the chain of evidence wherever it leads. I’ve encountered too many positive anecdotes from reliable sources to simply dismiss this alternative therapy. It’s also important to keep in mind that, if nothing else, homeopathy is typically believed to have a low potential of adverse effects. Couple that with the very real possibility of a placebo-effect and I think you have a novel option that should not be dismissed out of hand.

The only reasonable way to evaluate homeopathy in an objective manner is to get right down to the science that refutes and supports its use. Over the past 20 years or so, there have been numerous studies both pro and con on oral and topical arnica. Below, you’ll find a listing of the major trials that I found while researching the topic.

• Jan-Feb 2008 Journal of Alternative and Complementary Medicine – A “randomized double-blinded, parallel-group study” found that Arnica D4 was as effective as an anti-inflammatory medication (diclofenac) in patients recovering from foot surgery. Mobility, one aspect of healing, was superior in the arnica treated patients. However the diclofenac patients reported greater pain relief. Arnica D4 was “significantly better tolerated than diclofenac”. (1)
• Jan 2007 Rheumatology International – A topical arnica gel was comparable in efficacy to an ibuprofen gel in the management of hand osteoarthritis in a group of 204 patients. Those using the arnica gel exhibited a slightly lower incidence of adverse effects (4.8% vs. 6.1%). (2)
• Jan 2007 Homeopathy – A homeopathic arnica preparation resulted in “a significantly larger drop in pain score” in a 14 day evaluation of post-tonsillectomy related pain in 190 patients. In this case, the dosage and potency of arnica used was “Arnica 30c 2 tablets 6 times in the first post-operative day and then 2 tablets twice a day for the next 7 days”. (3)
• Dec 2006 Complementary Therapies in Medicine – A review of three randomized, placebo-controlled, double-blind, sequential clinical trials revealed a “trend towards less postoperative swelling compared to patients receiving placebo” in a group of 227 men and women recovering from knee surgery. (4)
• Oct 2003 Research in Complementary and Classical Natural Medicine – Arnica demonstrated superiority over placebo in reducing bleeding (hematoma) and pain in relation to varicose vein surgery in 60 patients that were followed for 14 days post surgery. Those receiving a product known as ARNICA D12 reported pain improvement of 43.3% vs. 27.6% in the placebo patients. (5)
• Oct 2003 Homeopathy – Eighty-two marathon runners were given an arnica homeopathic medicine (Arnica D30) or a placebo prior to and post long distance running. The arnica athletes exhibited a lesser degree of muscle soreness directly after the marathon. However, blood tests failed to reveal any change in cellular damage as measured by alterations in muscle enzymes. (6)
• Sept-Oct 2002 Advances in Therapy – A “fresh plant gel” derived from arnica was described as being a “safe, well-tolerated, and effective treatment of mild to moderate osteoarthritis of the knee”. In that evaluation, 76% of the participants said they’d use the arnica gel again. (7)
• Mar-Apr 2002 Alternative Therapies In Health and Medicine – This double-blind, placebo-controlled study utilized both oral and topical arnica in patients who underwent carpal tunnel release surgery. After two weeks of the respective treatments, the participants using the arnica (vs. placebo) noted a “significant reduction in pain”. However there were no improvements re: grip strength or wrist circumference (a measure of swelling). (8)

• Feb. 2010 British Journal of Clinical Pharmacology – A homeopathic remedy containing Arnica montana and Bryonia alba failed to improve bleeding, inflammation, myocardial ischaemia (reduced blood flow to the heart) or pain associated with aortic valve surgery. (9)
• Feb. 2008 British Journal of Clinical Pharmacology – A combination of the homeopathic remedies (Arnica montana 5 CH, Bryonia alba 5 CH, Hypericum perforatum 5 CH and Ruta graveolens 3 DH) was “not superior to placebo in reducing morphine consumption after knee ligament reconstruction”. (10)
• Feb 2003 Journal of the Royal Society of Medicine – Non-significant and differing effects were discovered when two arnica preparations (arnica 6c and arnica 30c) were compared to placebo in patients recovering from carpal tunnel surgery. The conclusion of the study states that, “The results of this trial do not suggest that homeopathic arnica has an advantage over placebo in reducing postoperative pain, bruising and swelling in patients undergoing elective hand surgery”. However, it should be noted that the interpretation of the study results has been an issue of controversy. This is especially true re: the arnica 6c supplement which did yield somewhat favorable results in comparison to the placebo. (11)
• Sep 1998 Clinical Journal of Pain – A homeopathic arnica supplement (Arnica 30X) and placebo was studied in a group of 519 long-distance runners. No meaningful changes were found between the groups based on the severity of post-race muscle soreness or “race time”. (12)
• Feb 1997 Journal of Royal Society of Medicine – Seventy-three women were asked to take a homeopathic arnica preparation (arnica C30) or an identical looking placebo pre and post hysterectomy. The authors of the trial concluded that, “arnica in homeopathic potency had no effect on postoperative recovery in the context of our study”. (13)

It’s unlikely that many detractors or supporters of homeopathy will make a point of bringing to light studies that conflict with their own perspective. But I want you to have both sides of the story. So rather than offering you my personal opinion about arnica, I invite you to come to your own conclusion – based on the facts. Please keep in mind that you should always consider differences in dosage, potency and types of arnica used in the studies I’ve cited. My only suggestion is that if you decide to try an arnica remedy, consider selecting a product that has at least some evidence to back it up. By doing so, you’ll be making a more informed decision and possibly increasing the likelihood that you’ll find similar positive results.

Be well!

JP