Comfrey is a pretty miraculous herb. The roots and leaves contain a substance called allantoin, which promotes healing and tissue regeneration. Applied to wounds, it reduces inflammation and promotes healing of damaged or injured tissues.
Taken internally, comfrey has been used to treat a wide variety of ailments ranging from bronchial problems, arthritis, stomach pains and diarrhea, even asthma. But it isn't recommended to be taken internally due to the presence of dangerous, cancer-causing compounds.
However, it is widely applied externally in ointment form and is great for bruises, sprains, severe burns, dislocated bones, joint pain, acne, and other skin conditions.
Comfrey is purported to have bone and teeth building properties in children, as well as to be beneficial in treating many "female disorders." It was even believed way back when that comfrey could repair the hymen and thus "restore virginity." What would Madonna say to that?
It's a great idea to keep some comfrey along with arnica in your medicine cabinet if you prefer to use natural pain relieving remedies. Try this one from Burt's Bees called Dr. Burt's Res-Q Ointment for only $5.