Sometimes called knitbone or All Heal, comfrey (Symphytum officinale L.) has been used for centuries to support bone, wound and lung healing, and at one time was recommended as a tea to soothe digestive issues. These days it’s also often recommended for:
- Soothing sprains, bruises, swelling, minor shallow-cut skin injuries and burns
- Easing tight muscles
- Boosting softness and shine when used as a hair rinse
- Moisturizing skin, which is why it’s incorporated into many skin serums and creams
Comfrey is rich in a compound called allantoin, which supports cell formation and granulation, also known as the creation of new tissue and microscopic blood vessels during the healing process.
Is comfrey safe?
Although it has been traditionally used both externally and internally, recent documentation of serious liver damage from drinking comfrey tea has prompted many herbalists to stop recommending the internal use of comfrey. External use of comfrey is still considered safe, though, so comfrey shouldn’t be thrown out of your herbal toolkit altogether.
The problem with comfrey is that every plant contains varying levels of several kinds of pyrrolizidine alkaloids, or PAs. PAs cause veno-occlusive liver disease in some people, a condition where the breakdown of the PAs release pyrroles that damage the veins in the liver that eventually leads to scarring and clogging (1).
This isn’t based on some petri dish or lab-rat study…these are real people and veno-occlusive liver disease can – and has been – fatal. However, those are individual occurrences, and no human clinical trials can be done to test the safety of comfrey due to the potential risks. (2)
In addition, some herbalists argue that the risks have not been properly assessed because there are several kinds of comfrey – common comfrey (S. officianale), prickly comfrey (Symphytum asperum) and Russian comfrey (S. uplandicum) – and it’s unclear which one was consumed in the cases that reported negative effects. Certain cultivars are thought to be lower in PAs than others, but more research is needed to confirm that.
The chances of someone getting liver occlusion from PA ingestion can’t be predicted. Liver occlusion is more likely to occur in people with compromised livers or people with malnourishment, but it can occur in anyone, any age, any time. On the other hand, some people can ingest comfrey and never get an occluded liver.
The entire comfrey family contains PAs, including the common garden companion borage. PAs are in the largest amounts in the root, and lowest in the oldest leaves. Other medicinal plants with PAs are the lung-remedy coltsfoot, and the recently discovered presence in immune supporting boneset (Eupatorium perfoliatum). The aster, pea, and orchid families also contain PAs (over 6,000 plants).
This debate is compounded by the fact that not all PAs are dangerous. Of the 650+ PAs currently known, non-toxic PAs are found in Echinacea and other medicinal aster family species. Coltsfoot (an antitussive herb) PAs are rumored toxic, but many attribute this to mistaken identification of a known toxic look alike, Petasites, and not coltsfoot. Coltsfoot PAs are mostly the non-toxic kind, but it does have extremely small amounts of the known hepatotoxic PAs. (1) Some herbalists will use coltsfoot long term; some will use it short term; some won’t use it with pregnant women/children; some won’t use it at all.
Should I drink comfrey tea?
The Botanical Safety Handbook, 2nd Edition, lists comfrey as Class 2a, 2b, and 2c: which means that it is recommended for external use only, and not for use in pregnancy or nursing. Comfrey is not recommended for use with deep wounds or unset bones.
Alternatives to comfrey tea for internal use
Comfrey was historically recommended internally to support healing when there is a dry cough or connective tissue injury (bone and skin). Fortunately, there are alternative herbs for both of these situations that don’t pose the same risk as comfrey.
Mullein leaf and marshmallow root can be taken together as a moistening, healing, lung-supportive remedy when a dry cough is present. To make a simple tea, pour 1/2 ounce of each into a jar and steep in 1 quart of lukewarm/cold water for 4-8 hours, then strain and drink.
For bone or other connective tissue injuries, consuming foods that provide nutrients for healing can go a long way. Bone broth, ample protein, healthy fats, foods and herbs high in B-vitamins, vitamin C, vitamin E, bioflavonoids, and minerals can be consumed during an injury, as well as getting adequate sun exposure for Vitamin D along with the benefits of infrared light. Comfrey can be used externally to support healing as well.
How to use comfrey externally
Although ingesting comfrey is not recommended, using comfrey externally is considered safe and can be very helpful for supporting the healing process with breaks, sprains, and strains, as well as minor shallow-cut skin injuries and burns. (3) It’s even been shown to ease tight muscles and support a healthy inflammatory process. (4)(5) Comfrey roots are the most powerful, followed by young leaves, with older leaves considered the least powerful.
Some people do get a skin rash reaction from comfrey leaves, so be careful during your first time handling them or using remedies made from comfrey leaves.
Both the leaves and roots can be used to make external comfrey remedies, often in either an oil, salve, or plaster. It’s best to use these acutely, no more than 4-6 weeks at a time, to avoid toxicity issues for any comfrey that gets into the blood stream through the skin (although chemically speaking PAs have very low solubility in oils, so comfrey oils and salves should be low in PAs.) (1)
Where to buy comfrey oil and salve
Below you’ll find recipes for making comfrey oil and salve at home, but if you don’t want to DIY here are some good pre-made options:
- Organic comfrey oil
- Dr. Christopher’s Comfrey Ointment (Contains the same ingredients as a traditional salve with just a little more oil and a little less beeswax)
How to make comfrey oil
The most common way of using comfrey externally for connective tissue injuries or small wound healing is through comfrey-infused oils.
Ingredients
- Organic dried comfrey leaves or comfrey roots
- Olive oil (Or another oil that you prefer. Almond and avocado are good options, as is jojoba)
Instructions (Slow Method)
This is the traditionally preferred method because it is thought to preserve the delicate constituents found in comfrey (and other herbs) best. However, sometimes it’s just not practical to wait 4-6 weeks for a batch, so I’ve also included a faster method below.
- Place comfrey leaf or root in a clean, dry glass jar.
- Next, pour in the oil – add enough so that the comfrey is covered by about one-half inch of oil. The reason this is done is that herbs expand as they soak in the liquid, so you add extra to ensure that they stay covered. Comfrey root will stay at the bottom so it’s easy to tell how much to add, but comfrey leaves float so it’s a bit more challenging. What I do is use my thumb to mark the top of the dried comfrey in the jar before I add the oil, then add about 1/2 inch above that.
- Cover the jar with a tight fitting lid and give it a good shake. Place the jar in a paper bag and store near a warm, sunny window. (Some people skip the paper bag, but others believe it helps protect some of the valuable constituents found in comfrey from breaking down due to UV light.) Give the jar a good shake when you walk by it every day.
- Once the oil has been infusing for 4-6 weeks, strain out the herbs and pour the oil in a clean, glass jar. Store in a cool, dark cabinet until needed.
Instructions (Quick Method)
- Place comfrey in a clean, dry glass jar.
- Next, pour in the oil – add enough so that the comfrey is covered by about one-half inch of oil. Comfrey root will stay at the bottom so it’s easy to tell how much to add, but comfrey leaves float so it’s a bit more challenging. What I do is use my thumb to mark the top of the dried comfrey in the jar before I add the oil, then add about 1/2 inch above that.
- Cover your jar with cheesecloth (or a paper towel that is cut into a small square) and secure it with a rubber band.
- Place a kitchen towel in the bottom of your slow cooker and place your jar inside. Add enough water to cover about half the jar and set to the lowest setting for 4-24 hours.My slow cooker has a warm setting so I can infuse it at a very low temperature for 24 hours, but for slow cookers that only have a “low” setting instead of a “warm” setting, I recommend only infusing for 4-8 hours. Leave slow cooker uncovered and allow to infuse, adding water if needed to keep the slow cooker basin from drying out.
- Strain out the oil using cheesecloth and pour the oil in a clean, glass jar. Store in a cool, dark cabinet until needed.
How to make comfrey salve
Comfrey oil doesn’t have to be turned into a salve. However, some people prefer the transferability ease of salves. Also, oils are messy and can attract dust and dirt, so outdoor use of plain oils is usually not practical. To turn the above comfrey oil into a salve, follow this method:
Ingredients
- 4 ounces comfrey infused oil (make your own using the recipe above or buy it here)
- 1/2 ounce by weight beeswax (about 2 tablespoons grated, packed beeswax)
- 25-50 drops essential oil, optional (lavender, frankincense, chamomile and tea tree are good choices)
Instructions
Gently heat the beeswax in a double boiler. (If you don’t have a double boiler you can use a stainless steel bowl set inside a pot of boiling water.) When the beeswax is melted, add in the comfrey oil. Allow it to warm up for 30-60 seconds, then stir until the beeswax and oil are thoroughly mixed. If you’re adding essential oils, wait until the mixture has cooled just a little and then stir them in.
Pour your salve into a clean, dry container and allow to cool – I used three of these 2 ounce tins. Now you’re ready for the next bug attack, bee sting, scrape, etc.
How to make comfrey plaster
If you want to avoid the time and effort of oils and salves, comfrey leaf and root plasters can be placed directly on unbroken or unabraded skin. Use an immersion blender, regular blender, or just scissors and mortar and pestle to crush the comfrey leaves into a pulp. Then wrap them in gauze, paper towels, or cheese cloth, or place them directly on the skin.
If you live in an area where comfrey only grows part of the year, you can freeze plasters to be used as needed. To freeze, put the gauze, paper towels, or cheese cloth into a freezer-safe container and freeze them for future use.
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Have you used comfrey before?
Please tell me about your experience in the comments below!
About the authors: This article was co-authored by Heather Dessinger and Dr. Lori Valentine Rose (PhD). Dr. Rose, PhD is a college biology, nutrition, herbal, and wellness instructor, Certified Nutrition Professional (CNP), Registered Herbalist with the American Herbalist Guild, and is Board Certified in Holistic Nutrition. She created, developed, and instructs the Hill College Holistic Wellness Pathway, the most thorough, affordable, degreed wellness program in the country. She loves spreading love and light, and helping others feel awesome on the inside and out so they can live their dreams and make this world more awesome!
Sources for this article:
1. Ganora, Lisa. (2009) Herbal Constituents: Foundations of Phytochemistry
2. Case Reports of Toxicity with Internal Use of Comfrey. Retrieved from Comfrey Central
3. Barna, M et. al. (2007) Wound healing effects of a Symphytum herb extract cream (Symphytum x uplandicum NYMAN: ): results of a randomized, controlled double-blind study. Retrieved from Europepmc.org
4. Kucera, M et. al. (2005) Topical symphytum herb concentrate cream against myalgia: a randomized controlled double-blind clinical study. Retrieved from Europepmc.org
5. Grube, B et. al. (2007) 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 trial.. Retrieved from PubMed
If you purchase Comfrey Infused Oil from the Amazon Link, would you still use 4 oz – the same as the oil you created in the Salve recipe above?
Yes 🙂
A friend of mine introduced me to Comfrey and gave me a plant about 5 years ago. I have made comfrey salve ever since. When my daughter had a bad break to her arm up near the shoulder she had a deep purple bruise that went all the way to her elbow. I put comfrey salve everywhere I could reach and at the next recheck the Dr was surprised to see how fast the bruising had gone away, and confused as to why the underside was still purple (where I couldn’t reach without hurting her).
My parents also use comfrey salve on their sore joints and say it really helps with arthritic pain. My Mom was so impressed that she got a comfrey plant and makes and gives away comfrey salve to her friends. I use it for minor scrapes and cuts with the kids and for dry skin in the winter months for myself.
Hi,I just want to know if you make all the salve recipes you have on your site. It’s just that all are indicated for bug bites,cuts and scrapes etc. I’ve made the plantain and calendula salves. Is there a completely separate application for this which will warrant making another salve?
Hi Sharifa, there is often a lot of overlap in the uses for different herbal salves. I do make all of them at different times depending on what I’m using them for and what I have on hand, but you can easily get by with just a few of them. One of the main reasons I post all the different recipes is so that you can make what works for you based on the herbs that grow in your area or are available at your local herb shop/natural health food store. 🙂
I used to be able to buy a water-based comfrey gel that was absolutely amazing! I used it on myself and my animals. I was able to buy at wholesale in an 18 pound bucket from a business called the comfrey gal. They ended up going out of business overnight because the man that processed the comfrey base passed away. I would LOVE to be able to get (or make) this again. I even put some in my I when I raised up too quickly and bumped my eye into the corner of a wooden mantle. My eye had gotten blood red immediately and just missed the Iris. Within a week it was back to normal coloring. I’ve watched it heal a nasty cut on my finger from electric hedge clippers. It took swelling down and healed from the inside out beautifully. I had cut halfway through, right to the bone, but I did not go to the hospital or get stitches or anything. You can barely see the scars. I am literally devastated that I cannot get it anymore.
Hi, I’ve made the plantain and calendula salves. All are indicated for bug bites,cuts and scrapes. So do I need to make this as well or will those two suffice? Does the comfrey salve have a completely different application as well?
Plantain and calendula would be my first choice for bug bites, scrapes, etc. This salve would be my first choice for supporting the body’s natural healing process after a break or sprain.
Hi Heather,
I investigated comfrey tea a few months ago and could have sworn the liver toxicity was from someone testing it on rats by feeding them a pound of comfrey a day, not from humans. I was looking into it as a tea infusion to help demineralization teeth and help with cavities. Thanks for the recipes on salves!
Sarah, I don’t think that the rats were fed a pound of comfrey per day but they were given copious amounts of the alkaloids found in comfrey causing tumors and cancer in ‘tiny’ rats.
When the tests were re-done using the entire plant the results were quite different showing no tumors or cancer.
Bottom line if comfrey is consumed in its whole state and within normal ranges it is OK to take for short periods of time.
(The Little Herbal Encyclopedia” by Jack Ritchason ND (3rd ED))
I read the site that refers to the toxicity of comfrey and the last study is indicated at being done in 1992 not ‘recent’ by any stretch of the imagination. Do you know of or have anything more recent that the 1992 study?
I also noticed this and the source listed was written in 2004 saying there was no indication of ingestion causing the issues listed.
I have comfrey in my garden. Can I use fresh comfrey for the oils and salves? How do you dry it? I’ve only made poultice with it.
Fresh comfrey leaves and root contain a good deal of moisture which, in time, can mold in your salve. Take your leaves or thinly sliced root and dry them, either in a dehydrator or by putting them in a very warm place. I hang the leaves inside a paper bag in my attic, the root slices are laid on a screen, covered with cheesecloth, and left in the attic where they dry up really fast.
I used a similar recipe to make comfrey salve with great results. I broke my wrist several months ago, the main break was plated and screwed, but 2 smaller fractures weren’t. Six weeks post surgery I still had a lot of inflammation and very little movement. Within 30mins of applying the salve the constant ache subsided and the inflammation was greatly reduced by the next day. This made my rehab exercises much easier. My therapist was very surprised.
I look forward to making your other recipes now I have found your site, thank you for sharing.
I have a comfrey plans growing in my garden and I use it for all pains and bruises, cuts and injuries. Few weeks ago my son had his wisdom teeth removed and the wounds were deep and needed stiches. He was told to take strong prescription medications for pain and was told that pain will get worse by 4th day but will get better with in 2-3 weeks. On the 4th day he should start rinses with syringe of the hole to make sure no food gets in there. So when we got home I took some dry comfrey roots and boiled for a couple mins cooled it off and saturated the gauze that was given to him to stop the bleeding and put it behind his cheek. As the numbness started to wear off he started to feel pain but he continued to use comfrey root tea and some ibuprofen and kept renewing his old gauze with new/clean one. By the 2nd day he was much better never needed prescription medications for pain and on 4th day when I decided to help him to flush the hole I didn’t find anything and stiches fell off. On 5th day he was in school like nothing ever happened. I thought it was a miracle. This is only one of the miracle that comfrey did but there were many more.
A while ago I attended an herb conference and one of the speakers praised the use of comfrey for breaks and wounds.
When I arrive home from the conference, there was a note that my husband had injured himself while using a power tool and was at the local hospital emergency room. I rushed there and the only treatment he’d been given was a tetanus shot, a pain reliever and left soaking the finger in saline, waiting for a doctor to arrive. The doctor arrived about the time I did. The end of the bone was visible. The doctor said there was not ample skin to suture over the end of the finger and recommended he come to his office on Monday and he would remove skin from another location on his body and graft it to the finger.
I made a comfrey solution in which he soaked the finger the rest of the weekend, other than during sleep, when we used a poultice.
So much progress was made over the weekend that we didn’t go to the doctor on Monday. Within two weeks of following the regimen, the skin had grown over the end of his finger. We never went back to the doctor again for the injury.
I would like to make the comfrey oil to make a salve, but I’m wondering how much comfrey to use?? I didn’t see where it said an amount. Did I miss it?? Thanks!
The salve recipe is at the bottom of the post 🙂
I once smashed my thumb with a hammer, hard. I took a comfrey leaf filled my rubber gloves thumb, pulverized the leaf inside, with same hammer, stuck my poor thumb inside and left the glove on till the next morn. When I awoke my thumb was normal, the nail didn’t even turn black and I never lost it. Awesome gift from God.
My friend’s son was trying out for the olympic bobsled team. He smashed his elbow in a wipeout breaking the olecranon. His mother boiled comfrey root, soaked a flannel cloth, covered the injury with the flannel, then plastic wrap every night. The elbow healed fast. The only bruising was near the hand and shoulder. The pain was minimal and was relieved quickly. Physiotherapist was impressed and worked on regaining range of motion. The mother was very impressed at my recommendation.
A friend fell injured his leg muscles. I told him about comfrey. I gave him some powdered root. He mixed it with water, heated it and then put it on top of the painful spasm and then covered it with a wet cloth, then plastic wrap. It helped the pain immediately. He left it on for about 5 days untouched, after which when he took it off he had blisters on the skin. So beware of leaving the herb directly on the skin too long without relief. Always check at least daily, how any injury is doing. The powdered comfrey root was from Bulgaria. This was the first reaction I have ever seen with comfrey in using it for many years.
Do you know if the comfrey from Bulgaria was Symphytum Officinale?
In 1983, when my daughter was 15 months old, she broke her leg. The doctors said she would be laid up for 6 weeks and they would then take another xray to see how it was healing. I decided to give her 1x1000mg of vitaminC, 1x garlic tablet and 1x comfrey tablet per day. After 3 and a half weeks she was energetic enough to the point of me asking them to take an xray. 2 days later they did just that (to keep me quiet, I’m sure) Nevertheless, to their utter amazement, they released her as it had completely healed but not before the Registrar, the dietitian and a number of others had asked me about the comfrey and the treatment I had given her.
I had a bad gash to a finger caused by a knife. The vet suggested a couple of stitches from a Doctor. I tightly bound the finger to stop bleeding and then my wife applied comfrey a few hours later. Over the next three days we changed dressings nightly and the result was the gash healed from the base and left very little scarring. Impressed.
Can I use coconut oil in the quick method? Thanks!
Yep!
Can I use fresh leaves from my garden to make the oils with, as I am doing with plantain?
Yes, definitely!
Thanks! Putting it on my to do list for tomorrow. Rain coming in later in the day.
I am planning on storing most of the oil till I need (and have time) to make some salve. Should I put a bit of Vit E oil in as a preservative? If so, how much? I have 8-9 oz of oil. Same with my plantain oil.
TY, Deb
Hi, how long does this keep? 🙂