Overview

Comfrey (Symphytum officinale) is a plant with yellow or purple flowers found in Europe, Asia, and North America. It contains chemicals that are poisonous.

Comfrey contains chemicals called pyrrolizidine alkaloids (PAs), which can cause severe liver damage. It also contains chemicals that might reduce swelling.

Despite safety concerns, some people use comfrey for bruises, osteoarthritis, sprains, and other conditions, but there is no good scientific evidence to support these uses.

The US FDA has recommended that all comfrey products that are taken by mouth be removed from the market due to serious safety concerns. Don't confuse comfrey with black root or bugle. These are not the same. Also don't confuse it with foxglove, which looks similar to comfrey before it blooms.



Uses & Effectiveness

We currently have no information for Comfrey overview.

Side Effects

When taken by mouth: Comfrey is likely unsafe. It contains chemicals called pyrrolizidine alkaloids (PAs), which can cause liver damage, lung damage, and cancer. The FDA has recommended that all comfrey products that are taken by mouth be removed from the market.

When applied to the skin: Comfrey is possibly safe when used on unbroken skin in small amounts for less than 6 weeks. But the poisonous chemicals in comfrey can pass through the skin, so it is possibly unsafe to use comfrey on broken skin or to apply large amounts for more than 6 weeks.

Special Precautions and Warnings

When taken by mouth: Comfrey is likely unsafe. It contains chemicals called pyrrolizidine alkaloids (PAs), which can cause liver damage, lung damage, and cancer. The FDA has recommended that all comfrey products that are taken by mouth be removed from the market.

When applied to the skin: Comfrey is possibly safe when used on unbroken skin in small amounts for less than 6 weeks. But the poisonous chemicals in comfrey can pass through the skin, so it is possibly unsafe to use comfrey on broken skin or to apply large amounts for more than 6 weeks.

Pregnancy and breast-feeding: Comfrey is likely unsafe when taken by mouth or applied to the skin while pregnant or breast-feeding. The PAs in comfrey are absorbed through the skin and might cause birth defects. Avoid use.

Broken or damaged skin: Don't apply comfrey to broken or damaged skin. Doing so might expose you to large amounts of the chemicals in comfrey that can cause liver damage and other serious health effects.

Liver disease: Comfrey might make liver disease worse. Don't use comfrey if you have any liver problems.

Interactions

    Moderate Interaction

    Be cautious with this combination

  • Medications that can harm the liver (Hepatotoxic drugs) interacts with Comfrey

    Comfrey might harm the liver. Some medications can also harm the liver. Taking comfrey along with a medication that can harm the liver might increase the risk of liver damage.

  • Medications that increase break down of other medications by the liver (Cytochrome P450 3A4 (CYP3A4) inducers) interacts with Comfrey

    Comfrey is changed and broken down by the liver. Some drugs increase how quickly the liver changes and breaks down comfrey. This could change the effects and side effects of comfrey.

Dosing

Comfrey contains chemicals that cause serious liver damage when taken by mouth. The FDA has recommended that all comfrey products that are taken by mouth be removed from the market.

Topical creams containing comfrey root extract have most often been applied to the skin by adults for up to 3 weeks. Don't apply comfrey products to broken skin or use large amounts on the skin, long-term. The poisonous chemicals in comfrey can be absorbed through the skin. Speak to a healthcare provider to find out what dose might be best for a specific condition.
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CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

This copyrighted material is licensed from Therapeutic Research Center, LLC. Information from this source is evidence-based and objective, and without commercial influence. For professional medical information on natural medicines, see Natural Medicines Comprehensive Database Professional Version.
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