What is Comfrey?
Comfrey is an herbal ingredient also known as Russian comfrey, common comfrey, prickley comfrey, bruisewort, slippery root, boneset, knitbone, wallwort, healing herb, black root, salisfy, and Symphytum officinale.
It has been used externally to treat wounds, bruises, heal muscles and reduce inflammation associated with sprains and bone fractures. It has also been taken internally for stomach upset, diarrhea and hemorrhoids, as well as used a gargle for sore throats and gum disease.
Comfrey can be found in a number of products from brands such as:
What are the dangers?
On July 6, 2001, the US Food and Drug Administration (FDA) issued a warning to the manufacturers marketing a product containing comfrey, strongly recommending that they remove the product from the market and alert its customers to immediately stop using the product.
The comfrey plants contain pyrrolizidine alkaloids, which are potent toxins to the liver, as well as other tissues, and therefore may pose a serious health hazard. There is also evidence that they may be carcinogenic (cancer-causing). Since the use of comfrey has been associated with serious liver damage, use of comfrey on broken skin or taking it internally is not recommended.
What are the side effects?
Comfrey may cause serious allergic reactions. Stop using Comfrey and seek emergency medical attention if you develop difficulty breathing, hives, or swelling of your face, lips or tongue.
Notify your doctor immediately if you develop any of the following, as they could be early signs of liver damage:
nausea or vomiting
loss of appetite
yellowish appearance to your skin or eyes
clay colored feces