What is it?
Comfrey is an herbal medicine used on the skin for bruises, wounds, muscle aches and pains, and sprains.
Other names for comfrey include: prickly comfrey, Russian comfrey, Symphytum officionale , S asperum , S x uplandicum
Ask your doctor, nurse, or pharmacist if you need more information about this medicine or if any information in this leaflet concerns you.
Tell your doctor if you
Talk with your caregiver about how much comfrey you should take. The amount depends on the strength of the medicine and the reason you are taking comfrey. If you are using this medicine without instructions from your caregiver, follow the directions on the medicine bottle. Do not take more medicine or take it more often than the directions tell you to.
To store this medicine:
Keep all medicine locked up and away from children. Store medicine away from heat and direct light. Do not store your medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down and not work the way it should work. Throw away medicine that is out of date or that you do not need. Never share your medicine with others.
Drug and Food Interactions:
Do not take comfrey without talking to your doctor first if you are taking:
Call your doctor right away if you have any of these side effects:
Other Side Effects:
You may have the following side effects, but this medicine may also cause other side effects. Tell your doctor if you have side effects that you think are caused by this medicine.
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4. Anon: British Herbal Pharmacopoeia. British Herbal Medicine Association, Keighley, UK; 1983.
5. Weston CFM et al: Veno-occlusive disease of the liver secondary to ingestion of comfrey. Br Med J 1987; 295:183.
6. Ridker PM et al: Hepatic veno-occlusive disease associated with the consumption of pyrrolizidine-containing dietary supplements. Gastroenterology 1985;88:1050-1054.
7. Weiss RF: Herbal Medicine. Beaconsfield Publishers Ltd, Beaconsfield, UK; 1988.
8. Lewis CJ: FDA advises dietary supplement manufacturers to remove comfrey products from the market. July 6, 2001. Available at: http://www.cfsan.fda.gov/~dms/dspltr06.html (cited 8/7/2001).
9. Grube B, Grunwald J, Krug L, et al: Efficacy of a comfrey root (Symphyti offic radix) extract ointment in the treatment of patients with painful osteoarthritis of the knee: results of a double-blind, randomised, bicenter, placebo-controlled study. Phytomedicine 2007; 14:2-10.
10. Predel H-G, Giannetti B, Koll R et al: Efficacy of a comfrey root extract ointment in comparison to a diclofenac gel in the treatment of ankle distortions: results of an observer-blind, randomized, multicenter study. Phytomedicine 2005; 12:707-714.
Last Updated: 6/13/2013
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