Symphyti radix (Comfrey root)

SUMMARY:
The herbal monograph selects and summarises scientific studies and textbooks regarding efficacy, dosage and safety supporting the therapeutic uses of comfrey root.
This herbal drug by definition consists of the dried rhizomes and roots of Symphytum officinale L.
Studies with its main characteristic constituents allantoin, mucilage polysaccharides, phenolic acids, glycopeptides and triterpene saponins are included.
The therapeutic indications are pain and swelling related to muscle and joints; acute myalgia in the back, strains, contusions and distortions, epicondylitis, tendovaginitis and periarthritis.
Administration of comfrey root addresses posology; its duration of use; contra-indications; special warnings; special precautions for use; interactions with other medicinal products; other forms of interaction; in pregnancy and lactation; its effects on ability to drive; undesirable effects; overdose.
In vitro experiments with comfrey root extracts demonstrate anti-inflammatory, woundhealing and antibacterial properties.
In vivo experiments with animals indicate anti-inflammatory and woundhealing activities.
A pharmacological study in humans concerned effects related to wound healing.
Several controlled clinical studies with topically applied comfrey root extract demonstrated its therapeutic efficacy in patients with sprained ankles, painful joint complaints and osteoarthritis of the knee.
Preclinical safety data for comfrey root were assessed in toxicity studies and indicated that 99% of pyrrolizidine alkaloids should be removed from its extracts.
Safety data were assessed in human studies. Adverse effects of topically used comfrey root extracts were limited to skin reactions.
The selection of literature cited in the monograph is aimed at bringing together relevant information about the possible physiological roles of comfrey root and its major constituents.KEYWORDS:

• Symphytum officinale L.
• Symphyti radix
• Comfrey Root
• Pain and swelling in muscle, joints; Myalgia in the back; Strains; Contusions, Distortions; Epicondylitis; Tendinitis; Periarthritis