Response to #4

Response to #4

4. Many of the studies cited in literature related to harmful effects of Symphytum officinale were performed on related species with higher Pyrrolizidine alkaloids content than Symphytum officinale.

Pathology 1991 Jan;23(1):35-8
The effects of comfrey derived pyrrolizidine alkaloids on rat liver.
Pyrrolizidine alkaloids extracted from Symphytum uplandicum were used to show the toxicity of comfrey. This Russian comfrey species is not sold or distributed in herbal formulas.

None of Dr. Christopher's original formulas include Symphytum uplandicum, or any other Symphytum species other than officinale.

Experientia 1980 Apr 15;36(4):377-9
Structure and toxicity of the alkaloids of Russian comfrey (Symphytum uplandicum N.), a medicinal herb and item of human diet.
Alkaloids extracted from this related species exhibited chronic hepatotoxicity in rats. This study was not performed with the whole herb of the correct species.

None of Dr. Christopher's original formulas include Symphytum uplandicum, or any other Symphytum species other than officinale.