We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission. Here’s our process.

Available research suggests that arnica can help reduce bruising. Arnica can be applied to the skin in the form of gels or lotions. It’s often taken in a homeopathic dose by mouth.

Though oral homeopathic arnica is believed to help with bruising, it’s listed as a poisonous plant by the Food & Drug Administration (FDA) and considered unsafe for oral ingestion.

Homeopathy remedies are so diluted that it’s unlikely poisoning will happen. In homeopathy, there’s a belief that the dilution makes the remedy more effective because of how it works on an atomic level. The FDA hasn’t approved any homeopathy remedies such as arnica, and hasn’t evaluated any remedy for effectiveness or safety.

The scientific name for arnica is Arnica montana. It’s also known as:

  • Mountain tobacco
  • Leopard’s bane
  • Wolf’s bane
  • Mountain arnica

The flower of the arnica plant has been used for hundreds of years for its apparent benefits. Traditionally, it’s been used to reduce pain, swelling, and bruising.

Arnica is often used in gel or lotion form. This can be applied topically to the affected area.

Despite the FDA poisonous plant designation, arnica is available as a safer, diluted homeopathic remedy. Homeopathic arnica often comes in the form of pills.

A 2006 study looked at the effect of homeopathic arnica on facial bruising. It found that homeopathic arnica may reduce the severity of bruising. A 2010 double-blind study looked at topical arnica and found that it reduced bruising.

More recently, a 2016 review looked at the effects of homeopathic arnica on pain and inflammation after surgery and found that it was both a safe and effective way to reduce bruising, swelling, and pain.

A 2014 review looked at lotion containing less than 10 percent arnica, and the authors concluded that there was insufficient evidence to suggest that these low doses of arnica can help with bruises. More research is needed on the effectiveness of doses higher than 10 percent as well.

Current research indicates that both topical and ingested arnica can reduce bruising. Arnica comes in the following forms:

  • gel
  • lotion
  • pain patches
  • tissue salts
  • pills
  • teas

Shop for arnica.

It’s important to note that homeopathic remedies aren’t regulated by the FDA, and neither is arnica tea. That said, most studies on homeopathic arnica have found it safe for use.

A 2000 study confirmed that, when ingested, arnica could interact with blood-thinning medications, such as warfarin. This is because arnica could make anticoagulants more potent.

Arnica is often used for pain management, but research on its effectiveness is mixed. One 2010 double-blind study looked at the effects of arnica on muscle pain in 53 subjects. It found that, when compared to a placebo, arnica lotion actually increased leg pain 24 hours after atypical muscle use.

However, a 2016 review of studies found that arnica is both safe and effective at easing pain after surgery. It concluded that homeopathic arnica could be a viable alternative to NSAIDs, depending on the condition being treated.

A 2017 review looked at the multiple possible benefits of arnica. In addition to reducing pain and bruising, arnica could have antibacterial, antifungal, and antitumor properties. However, these properties need to be studied further.

As mentioned, arnica is considered unsafe for ingestion by the FDA. Consuming arnica can lead to diarrhea, vomiting, nausea, and internal bleeding. It’s possible to overdose, even on homeopathic arnica.

A 2013 study documents the case of an individual who overdosed on homeopathic arnica and experienced vomiting and a temporary loss of vision.

According to the Memorial Sloane Kettering Cancer Center, you should avoid ingesting arnica if you’re pregnant or breastfeeding, as it can harm the fetus or baby. In one case, a mother drank arnica tea, and her 9-month-old nursing baby became lethargic 48 hours later. The baby was treated and his symptoms eventually disappeared.

You also shouldn’t ingest arnica if you’re on warfarin (Coumadin) or any blood-thinning medication.

It’s possible to be allergic to arnica, so do a patch test before applying arnica lotion to a large area of skin. If you’re allergic to sunflowers or marigold, it’s likely that you’re also allergic to arnica.

Topical use of arnica can lead to contact dermatitis in some people. Don’t apply arnica to sensitive skin or open wounds.

According to research, arnica might be able to reduce bruising and swelling when applied topically or taken as a homeopathic treatment in pill form.

Arnica also has a range of other useful medical benefits. Check with your doctor before using any type of arnica if you have any concerns.