Never take comfrey by mouth because it can cause severe health problems. Comfrey cream should not be used for more than 10 days in a row. Do not use comfrey cream on open wounds or broken skin.

FRIEND OR FOE: Comfrey has long been used medicinally and as a garden fertiliser, but concerns have been raised about the potentially damaging alkaloids it contains. Photo: JONATHAN CAMERON / Dominion ...