Comfrey (Symphytum officinale) has a long history of traditional use in herbal medicine, particularly in Europe and Asia. Historically, comfrey leaves and roots have been applied topically or used as rinses to promote healing of wounds, ulcers, and inflamed tissues, including those in the mouth such as the gums. Folk medicine practitioners valued comfrey for its purported ability to accelerate healing and reduce inflammation, which is why it has often been included in traditional remedies for oral health and gum support.

The primary constituents believed responsible for these effects are allantoin (a compound known to promote cell growth and tissue repair), mucilage (which soothes irritated tissues), and rosmarinic acid (which has anti-inflammatory properties). Despite its traditional use, scientific validation for comfrey’s efficacy specifically for gum health is limited. There are a few in vitro and animal studies that suggest allantoin and other comfrey constituents can support tissue repair, but well-controlled clinical trials on humans for gum health are lacking.

Additionally, comfrey contains pyrrolizidine alkaloids (PAs), compounds known to be hepatotoxic and potentially carcinogenic if ingested or absorbed in significant amounts. As a result, internal use of comfrey (including oral rinses) is discouraged or banned in many countries, and its use is generally restricted to topical applications on unbroken skin. In summary, while traditional use for gum support exists, robust scientific evidence and safety data are lacking.