Comfrey may Improve Back Pain

An ointment made from comfrey root extract may significantly reduce acute upper and lower back pain, according to a new study published in the British Journal of Sports Medicine.

Comfrey (Symphytum officinale) is a perennial herb native to Europe and Asia. The herb has traditionally been applied to the skin for inflammation, pain and wound healing, and has been taken by mouth for digestive, breathing and gynecological conditions.

In the study, 120 adults with back pain were randomly assigned to receive either 4 grams of the comfrey-containing ointment Kytta-Salbe® or placebo three times daily for five days. The participants' pain was measured using a visual analogue scale.

By the end of the study, pain intensity improved by about 95 percent in the comfrey group compared to just 37 percent in the placebo group. The authors also noted that pain was relieved quickly, usually in less than one hour after the ointment was applied to the skin.

The authors concluded that "comfrey root extract showed a remarkably potent and clinically relevant effect in reducing acute back pain." These findings support several earlier human studies that suggest comfrey-containing creams may reduce inflammation and pain associated with sprains and muscle injuries.

Although comfrey has been traditionally used both orally and topically, recent evidence suggests that the herb may contain cancer-causing compounds and may lead to liver damage. As a result, various countries, including the United States, have asked companies to remove oral comfrey products from the market, and topical products are required to advise consumers not to use on broken skin. Other countries, such as Germany, allow topical comfrey products with a label including the maximal daily allowable levels of pyrrolidizine alkaloids of 100 micrograms and maximal use over six weeks per year.

For more information about integrative therapies for pain, please visit Natural Standard's  Comparative Effectiveness database.

Comments

[P.F.]

This entry shows the importance of having the correct information about a treatment before using it. The article says people have taken the herb orally for digestive, breathing and gynecological reasons. Many of these people may have taken the herb without knowing about the risks of cancer. Herbal medicines unregulated by the Food and Drug Administration may be less clear about their risks. Therefore, it becomes the responsibility of the consumer to do their homework before using it.

[Dan H.]

I wonder if some people assume that integrative medicine, specifically herbs, are more likely to be safe than synthetic medications. Herbals are natural, simple and from the earth, whereas synthetic medicines are complicated, full of mystery and mass produced by machines. But this study debunks that assumption and shows that the safety of all medicines, no matter where they come from, is complicated.

[G.Fold]

I think it's wonderful that someone did a study on comfrey. I wonder who funded it -- was it Kytta-Salbe®? People trust pharmaceuticals because they are rigorously tested by the companies that make them, and their testing is regulated by governments. But I don't think herbal medicines always go through this testing. Therefore, herbal medicine may be useless or even, as in the case of oral comfrey, harmful, and people might not know about it. This article does a nice job defining this medicine's safety parameters.

[gg]

While it is great to see that comfrey may have potential benefits in patients with a difficult-to-treat condition (pain), comfrey also seems to be fairly dangerous when used improperly. Patients really shouldn’t use this without supervision of a practitioner. I agree with PF that patients should know what is appropriate and should do their homework before they begin taking something, but I think in this case, that is not enough. People taking herbs should really seek the help of an informed healthcare professional to prevent tragedies like the patients who have suffered from serious liver damage from comfrey.

[Trevor Fields]

A 95% improvement in pain symptoms is a significant result. I wonder what the exact extent of the back pain was in the study participants. Pain is such a subjective measurement that it is difficult to measure and prove undoubtedly that a difference exists. Regardless, 95% comparative to 37% is quite the jump in reported pain, so comfrey is likely to have a strong potential in alleviating acute back pain. If the efficacy of comfrey becomes well established, the next step is determining its exact carcinogenic potential. Studies would have to be done to ensure that strict guidelines of maximum dosages can be created in order to prevent any cancers from developing in comfrey-using patients.

[kelly]

I've definitely read a lot about the potential pain-relieving properties of comfrey. However, since there are some serious health concerns associated with its use, I'm not sure I would try it. I've personally found that acupuncture is great for relieving my neck/back pain.

[Lexi L]

How about capsaicin? I've heard that it helps improve different types of pain, particularly joint pain. Is it effective? Is it safe to apply to the skin?

[Warren Peace]

There are lots of over-the-counter options for easing back pain, such as BenGay and capsaicin, which do not carry risks of liver damage or cancer like comfrey does. I would like to see a trial that compares comfrey to these OTC products because I don’t think that comfrey will work as well. Also, no “p” values are given in this study (at least in the abstract that is available online), meaning the results may have never reached statistical significance.

[Les Payne]

Warren,

Where did you find that abstract for comfrey? I am a survivor of my youthful mistake: I took a dare and jumped from a cliff about 200ft above the reservoir below, and my legs folded under me at the last second breaking my back. I now have all kinds of new hardware in me, and I’m tired of being constipated from the pain pills. I have tried BenGay and capsaicin, with little to no relief, and I want to research this comfrey more before I try and buy some, especially if it may cause cancer. (I’m just tired of the pain.) Thank you for any help.

[Mel Loewe]

Capsaicin is a topical analgesic that is FDA-approved for the treatment of osteoarthritis, rheumatoid arthritis, diabetic neuropathy, post herpetic neuralgia and post-surgical pain. It may be helpful for simple back pain, but is not currently approved for that treatment. Capsaicin is safe to apply to skin, but should not be put on broken or irritated skin; so if you have any cuts, you shouldn’t put it on! It also tingles a bit when you first apply it; you definitely don’t want to get it in your eyes (by accidentally rubbing your eye after applying it), so wash your hands when you’re done.

[shannon t]

I wonder if the researchers will at some point examine the effects of this on low-back pain (LBP), which is a much larger problem. I guess this is because upper back pain is typically more a result of muscular injury or strain, whereas lower back pain can stem from issues that need to be addressed on a number of fronts -- from biomechanics, to posture, to ergonomics. Still, it would be interesting to see if there is any result with comfrey for LBP, if researchers can find people who are willing to buck the potential risks noted by the U.S. government regarding carcinogens and liver damage.

[Warren Peace]

Les, I cannot believe that you survived such a fall! Were any newspaper articles written about you? To answer your question, I found the abstract for comfrey at http://www.ncbi.nlm.nih.gov/pubmed/19460762?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum. Also, you might want to speak to your doctor and see if he can change your pain medications and optimize your doses before you start trying to self medicate. You should try to increase fiber intake for the constipation and try to use a laxative like Docusate. I am pretty certain that if prescription opiates are not enough to treat your pain, comfrey will not be potent enough to help your back pain (otherwise it would never be available over the counter)!

[Tanya Hyde]

Mel,

Great answer, but do you know how capsaicin works? If not I’ll tell you real quick. First you forgot that a person would have to apply it religiously 3-4 times daily, because it depletes, or empties, a thing in the skin called substance P (a part of the tachykinin neuropeptide family). Substance P is what can cause you to feel pain. Substance P is thought to be related to the transmission of pain information into the central nervous system, and by depleting this substance, you can alleviate some of the pain.

[TB]

I agree with Mel that there is the FDA-approved OTC capsaicin, which has already been approved clinically. I am not sure if comfrey root extract ointment is available OTC in the U.S. because I have not seen one. Patients could try the comfrey root extract if it is available for acute treatment, but because long-term efficacy and safety has not been seen beyond fice days in the study, patients should be advised not to use longer than that period. In addition, patients need to be advised to avoid any trigger that can cause their back pain, Relaxation therapy or physical therapy may be helpful.

[angel]

I agree with Mel that there is FDA-approved OTC capsaicin that has been approved clinically. I am not sure if comfrey root extract ointment is available OTC in the U.S., because I have not seen one. Patients could try the comfrey root extract if it is available for acute treatment but because long-term efficacy & safety has not been seen beyond 5 days in the study, patients should not be advised to use it longer than that period. In addition, patients need to be advised to avoid any trigger that can cause their back pain, such as relaxation therapy or physical therapy.

[Amiya]

I did a quick search to see if Kytta-Salbe (Comfrey-containing ointment) was available, and I came across another article discussing this same study. That article stated that the product used in the study was not available in the U.S. and is only sold in Germany. But I then found the Merck formulation on Amazon.com, so may be it is slightly different?

Also, here is the NS monograph for those of you who are interested in this product: http://www.naturalstandard.com/monographs/herbssupplements/patient-comfrey.asp?printversion=true?printversion=true. The monograph does discuss the anti-inflammatory and pain-relieving actions, along with the negative side effects.

[Dr. Eric Murphy]

I think natural remedies are exciting and worthy of further exploration. However, just because a substance is natural, doesn't mean that it doesn't have some of the same potential for dangerous side effects as drugs.

I'm a chiropractor in Round Rock, TX, and as such, I believe in alternative medicine. The traditional route isn't always the best route. I appreciate you taking the time to post this very interesting article.

Dr. Eric Murphy

http://www.dreric4u.com

[Amanda]

I think it's fine to use comfrey topically for short term and with no open wounds, but I do not think it's a good idea to take it orally because it may cause some toxicities in the body. In my opinion, there are other alternatives for back pain, such as capsaicin cream, heat wrap therapy, acupuncture or swimming.

[Carle]

According to the monograph on the NS Web site, comfrey is possibly safe when used topically short term. However, long-term topical use is considered likely unsafe. Oral use is considered likely unsafe as well because of side effects, such as liver toxicity, abdominal pain, inflammation of the lungs, ascites and carcinogenic effects, just to name a few. In many countries, oral comfrey has been removed from the market.

[tristan]

Comfrey does work to reduce pain. In this case, the back-pain-relieving effects are supported by the recent double blinded, randomized, placebo controlled multi-center study. According to the Natural Standard monograph, comfrey has a grade B level of evidence for minimizing pain and inflammation. Grade B means that comfrey and its use for these conditions (like for pain and inflammation) has good scientific evidence.

However, people should not take comfrey if they are allergic or hypersensitive to comfrey, its constituents, or members of the Boraginaceae family. It should not be used in children (younger than 18 years) because there is not enough scientific data to support its use.

[tt]

Chronic back pain is a growing complaint of many people these days. I was very surprised to read that about 95% of the comfrey group reported pain intensity improvement compared to 37% in the placebo group. I just wish the authors identified what they defined as “improvement." That clarified piece of information would help me to correctly interpret the effectiveness of topical comfrey.

[Jenny]

Were the results from this trial statistically significant? It would make sense that once this compound was associated with liver damage and cancer that the oral form would be removed from the market; but I am surprised that there is still a market for topical products, especially since there is such a health concern for the use of this herb. I am sure if this issue was publicized more, people would completely stay away from it. Why take such a big risk when there are potentially other options, including other herbals, to improve back pain?

[Gary]

Another plant extract that is found to help reduce pain! Wow, I know that opioids are derived from plants, and we all know how effective they are at reducing pain. This article also mentions that comfrey may have cancer-causing compounds. I wonder if the active analgesic compound in comfrey is also carcinogenic. If it isn’t, then maybe they can extract only that compound and check the side effect profile as a long-term study.

[tea]

Don't take comfrey internally without the advice of a medical herbalist. Prolonged ingestion could lead to liver damage and possibly cancer. Liver damage would be caused by the plant's pyrrolizidine alkaloids.

[Ryan]

How about prolotherapy? I heard this is an effective treatment for people experiencing back pain.