Comfrey is a shrub growing in parts of Europe, Asia, and North America. While it may help with wounds and joint pain, professionals warn against eating it due to the risk of liver damage.

Comfrey, also known as Symphytum officinale, can grow up to five feet tall. It produces clusters of purple, blue, and white flowers, and is famous for its long, slender leaves and black-skinned roots.

While comfrey is popular for its potential health benefits, it poses some risks. It contains compounds that can harm your liver.

As a result, some countries have banned the sale of oral comfrey preparations. Many experts also advise against using topical comfrey on open wounds.

In this article, read more about comfrey’s potential benefits, risks, and what the research says about this plant.

According to a 2019 review, comfrey has had widespread use on people and animals in traditional medicine for over 2,000 years. One of its most popular names, “knitbone,” comes from its potential benefits for sprains, burning, and bruising.

In traditional medicine, people have used comfrey to help with the following issues:

In traditional medicine, people may take comfrey by mouth or apply it topically using balms, ointments, and other preparations.

Root and leaf extracts from the comfrey plant contain chemical substances, including allantoin and rosmarinic acid, which may contribute to the plant’s anti-inflammatory and wound-healing effects.

Comfrey’s properties may offer benefits for various health issues.

Wound healing

Research in a 2024 review suggests topical preparations of comfrey may have positive effects on skin wounds by encouraging cell growth and regeneration.

The review suggests that the antioxidant effects of comfrey extracts may contribute to its wound-healing potential.

A 2024 study used a topical comfrey extract on 15 Wistar rats to investigate wound healing and skin regeneration.

The topical preparation containing 20% comfrey extract led to faster healing and complete healing, which the researchers suggest could be due to comfrey’s bioactive compounds.

Despite these potential benefits, more research is necessary, and you should speak with a doctor before applying comfrey to wounds.

Relieving joint pain

Studies involving humans suggest that topical comfrey creams may have pain-relieving effects that may relieve joint pain.

According to a 2019 review, traditional uses of comfrey have focused on joint inflammation and swelling as well as joint disorders and distortions.

Research in the review suggests comfrey may help to relieve the following osteoarthritis symptoms, which affect the joints:

  • pain, particularly in the morning and evening
  • stiffness
  • function limitations

However, some of the research suggests comfrey did not improve joint inflammation or cartilage breakdown, and several studies found that the participants experienced some side effects.

Professionals typically don’t recommend that you eat or take any form of comfrey by mouth, and most countries have banned oral formulations.

This is because it can be toxic due to the pyrrolizidine alkaloids that comfrey contains. Consuming comfrey can lead to acute liver injury, which can cause symptoms like:

  • jaundice
  • pain in the upper right abdomen
  • nausea
  • weight gain due to fluid retention

In some people, this injury may be severe and progress quickly to liver failure.

Topical application of products containing comfrey extracts may also cause side effects on the skin, including:

  • hypersensitivity
  • itchiness
  • rashes
  • irritation
  • burning

Most countries have banned oral comfrey, such as in capsules or teas. However, you may still be able to find topical formulations, such as:

  • ointments
  • creams
  • salves

These topical preparations may contain other ingredients, so it’s a good idea to read the label before purchasing.

You may be able to purchase topical comfrey preparations from health stores and pharmacies. Talk with your doctor before using them to learn more about the potential benefits and risks.

Some research suggests comfrey has potential beneficial effects for treating minor wounds and joint pain, but oral preparations of the plant may cause liver damage and failure. You should never take comfrey by mouth.

Potential side effects of topical comfrey preparations include skin irritation, burning sensations, and itchiness.

Always talk with your doctor before using products that contain comfrey. They can help you understand the potential benefits and risks, as well as any other potential treatments to help with your health issue.