Comfrey (Symphytum officinale) is a perennial herb native to Europe and Asia with a long history in traditional medicine. Common names like “knitbone” reflect its historical use for aiding the healing of sprains, bruises, and fractures. Today, interest in purchasing comfrey primarily revolves around its use as a topical remedy for physical discomfort.
Available Forms of Comfrey Products
Consumers encounter several distinct product forms designed for external use. Traditional formats include the dried leaf or root, typically used for homemade poultices. The root contains a higher concentration of active compounds than the leaf. Simpler options for topical application are prepared salves, creams, or ointments. These combine comfrey extracts with a base of oils and other ingredients to create a ready-to-use topical rub. Comfrey oil, an infused preparation, is also available for direct skin massage.
Another option is purchasing live plants or root cuttings, such as the ‘Bocking 4’ or ‘Bocking 14’ varieties. Gardeners grow the herb for its fresh leaves, which are used to make immediate-use poultices, and to ensure a consistent supply of fresh material.
Reputable Retail Sources
Sourcing comfrey from reputable retailers ensures quality and accurate labeling. Specialized herbal apothecaries, established online suppliers, and reputable supplement stores (physical or online) are reliable sources for dried herbs and prepared topical products. Consumers should look for manufacturers that adhere to good manufacturing practices and list all ingredients clearly. These vendors should provide clear documentation on the species used and confirm that products are intended for external application only. Avoiding unverified third-party sellers helps prevent the purchase of mislabeled or contaminated items.
For those interested in growing the plant, specialized nurseries offer root cuttings or crowns. It is advisable to seek out specific, sterile cultivars like ‘Bocking 4’ or ‘Bocking 14,’ as they are less likely to spread aggressively.
Essential Safety Warnings
Comfrey contains pyrrolizidine alkaloids (PAs), which are hepatotoxic and can cause serious liver damage. Ingesting comfrey (as a tea, capsule, or supplement) is strongly discouraged due to the risk of hepatic veno-occlusive disease. Regulatory bodies, such as the U.S. Food and Drug Administration (FDA), have advised manufacturers to remove dietary supplements containing comfrey from the market.
The concentration of PAs is significantly higher in the root than in the leaves. Topical products must carry clear warnings that they are for external application only and should not be used on broken skin, open wounds, or mucous membranes. PAs can be absorbed through compromised skin and still pose a risk to the liver. Always confirm the product is explicitly labeled for external use on intact skin.
Preparation and Topical Application
Traditional use involves creating a poultice or using a prepared product for localized relief of sprains, strains, and bruises. To make a poultice from fresh leaves, crush the material to a pulp to release beneficial compounds like allantoin. Spread this pulp onto a clean cloth.
If using dried comfrey, moisten the material with hot water to create a thick paste. The preparation is applied directly over the affected area of intact skin and typically left in place for 20 minutes to a few hours before removal. Prepared salves and oils are simpler, requiring only a small amount to be gently massaged into the skin. Avoid excessive or long-term application to any single area of the body.