What Is Arnica Gel, and Can It Really Help Reduce Pain?

Arnica gel is a plant-based remedy applied that, when applied to the skin, supposedly eases pain and relaxes sore muscles. Arnica gel, as well as arnica cream, is available over the counter, online, at drugstore chains, or at your local natural grocery store.

Because it's a homeopathic remedy, you might not be sure whether it's safe. It turns out the Food, Drug, and Cosmetic Act (FDCA) regulate homeopathic products like arnica gel. Still, the Food and Drug Administration does not evaluate the safety or efficacy of those products.

While some online users leave rave reviews, it's a good idea to get an overview of arnica gel, including what conditions it may treat and what the research says about it before trying it.

What Is Arnica Gel?

Arnica gel comes from the flowers of the arnica plant. 

"Arnica is an herb that mostly grows in mountain regions in Europe as well as in East Asia, Canada, and the northern U.S.," explained Sonia Batra, MD, a board-certified dermatologist and founder of Batra Dermatology in Santa Monica, Calif. "People use the plant's flowers to decrease inflammation from ailments such as a sore throat, insect bites, swelling, bruising, muscle pain, arthritis, and other general pain."

Arnica is closely related to the sunflower and common daisy, explained Kim T. Tran, PharmD, pharmacy manager with the Jackson Health System in Miami. 

"The plant contains an active ingredient, helenalin, which in small concentrations can be beneficial as an anti-inflammatory and analgesic," explained Dr. Tran.

While people often use it to treat many types of pain, arnica gel is mainly reserved for sprains and bruising, added Dr. Tran. It's applied to the affected area and massaged into the skin.

You can also take arnica orally, sold over the counter in tablet form. However, oral arnica is diluted, according to Dr. Batra. It's commonly used to treat a sore throat and pain after dental work.

Does Arnica Gel Work?

Arnica gel's effectiveness is controversial. Some homeopathic healthcare providers swear by its efficacy, as do many users. But there is limited scientific evidence. 

"Overall, studies do not show arnica gel to be a sufficient treatment for pain management or prevention of muscle damage," noted Dr. Batra. "There are a few studies that have reported improvement in osteoarthritis after several weeks of use and that have compared its effectiveness to that of ibuprofen."

For example, one study showed that a 20% arnica gel formula sped up the healing of bruises compared to a topical 5% Vitamin K formula.

Still, Dr. Tran warned that arnica gel isn't a magic fix for pain. 

"Though this may sound promising, further clinical studies need to be conducted in order for this to be a proven remedy," explained Dr. Tran. "The efficacy of helenalin for treatment of pain and swelling, when applied topically, is not supported by the currently available evidence at doses of 10% or lower."

For doses higher than 10%, more research investigating safety and effectiveness is required.

Is Arnica Gel Safe?

Though researchers arnica gel has not been widely studied, Dr. Tran said it is generally safe for use. Side effects of topical arnica are very rare and include redness, itching, and skin irritation. If you notice any of those symptoms, Dr. Train advised you to no longer apply the product.

Additionally, Dr. Batra added that topical arnica should not be applied to broken skin or mucous membranes, as it can cause irritation. If you have a ragweed allergy, you'll also want to take a pass. 

"If you are allergic to ragweed or other plants of the same family that arnica belongs to, taking arnica will trigger an allergic reaction similar to what you would experience if exposed to ragweed or one of those other plants," warned Dr. Batra.

Play it safe, and don't use arnica if you are pregnant or breastfeeding. 

Like many other homeopathic medications, "there are not enough studies to show effects on pregnant or breastfeeding patients," explained Dr. Tran. "Since its mechanism of action has only been theorized, it is recommended to be on the side of caution to avoid this product if you are pregnant or breastfeeding." 

And that same advice goes for both topical and oral arnica. 

One final word of caution about oral arnica: Almost all experts and health agencies recommend against using it at all, according to Dr. Tran.

A Quick Review

Some people praise arnica gel, but the scientific evidence evaluating its efficacy is pretty weak. Although, for the general population, the topical form of arnica gel is safe to try. On the other hand, Dr. Tran and Dr. Barta advised against using the oral version. 

If you're uncertain whether arnica gel is safe for you to use, consult your healthcare provider before trying it.