9. Symphytum officinale has demonstrated its safety through thousands of years of documented traditional use.
Comfrey is referred to in Materia Medica written for thousands of years. Dioscorides (200 AD), Lobelius (1570), Sarracenius's version of Dioscorides (1596),Gerald's Herbal (1597) and The Pharmacopeia Londinensis Collegarum (1668) all point to the extensive use of Symphytum officinale as a herbal remedy. All also mention that Symphytumofficinale was already established as a herbal remedy for some time. None of these early pharmacopeias and Materia Medicas give warnings of the herb's use and generally regard comfrey as a safe plant with high value.