Butterbur (Petasites hybridus) has been used to relieve headaches for centuries. But the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) has decided to pull all butterbur products from the UK market, on what appears to be extremely flimsy evidence. What’s going on?

Butterbur: a “serious risk” to health
Back in January this year, the UK’s medicines regulator sent a letter to herbal representatives asking them to voluntarily withdraw all unlicensed butterbur products from the UK market – which meant all food supplements, since no butterbur product has yet been registered under the Traditional Herbal Medicinal Products Directive (THMPD). It also warned consumers that, “Butterbur products have been associated with [40] cases of liver toxicity [in the literature]. Of these cases, nine were of acute hepatitis and two of the nine cases resulted in liver failure requiring transplantation.”

The long arm of Ron Law
While researching the relative risk of death associated with food supplements and other substances and activities, consultant Ron Law asked the MHRA for its scientific justification behind the butterbur decision. The MHRA responded by sending him a copy of a paper by Anderson et al [1], which the MHRA had helpfully highlighted in order to show its reasoning.

Flimsy evidence
Here are the key reasons why the MHRA decided to remove all butterbur products from UK shelves:

In its warning to consumers, the MHRA states that, “40 cases have been reported in the literature”. As it happens, the Anderson et al paper mentions these cases [1], which occurred outside the UK, but the MHRA itself is apparently unable to locate any original records relating to them. As such, the MHRA’s claim cannot be validated
The paper also refers to minor changes to liver duct structure that occurred during a 6-month toxicity study of Petadolex in rats [1] given a Petadolex dose equivalent to 60–100 times the maximum clinical dose!
It refers as well as to mild to moderate increases in liver enzyme levels in a 28-day rat toxicity study, at doses equivalent to 200–300 times the maximum clinical dose
Finally, the paper notes that reductions were observed in the levels of bile salt transporters in an in vitro experiment using human liver cells exposed to extracts containing different concentrations of one of butterbur’s active chemicals
Scientific fraud
So, it appears that the MHRA has pulled butterbur based on the findings of a single paper, not waiting for them to be expanded upon or even repeated. A paper, moreover, that reported potential toxicity in rat studies and test-tube experiments – so-called ‘preclinical’ studies that, as likely as not, are completely unrelated to what would happen in living, breathing human beings. Not to mention that those experiments used doses enormously in excess of anything a person taking Petadolex, or any other butterbur-containing product, will ever receive in real life. Nowhere does the MHRA appear to have considered that people have been using butterbur for centuries to manage headache, or even that its use is associated with significant benefits – only supposed risks.

Butterbur isn’t banned
But the MHRA still hasn’t added butterbur to the list of prohibited herbs in the UK, so, as yet, it’s not officially a banned herb. It seems butterbur may be being used as another scapegoat to justify further clampdowns on herbs, something we’ve been expecting as the UK’s ‘sell-through’ of unlicensed herbal products phases out.

Herbs – and food supplements – are safe
As we demonstrated last week, herbal products and food supplements are among the safest substances we consume. Yet, here we have products being removed from the market using a level of precaution that is simply ridiculous — while completely ignoring any benefits that consumers of those products might receive. Obviously, if the MHRA applied the same over-precautionary principle to mainstream medicines, not a single one would remain on the market!

Oddly enough, we can’t see that happening.

Call to action
Share this article widely and raise awareness of this insidious use of scare tactics on the part of regulators. Butterbur has not been banned – the evidence is too flimsy – but consumers and suppliers are being bullied by fearmongering. This is a picture we’re seeing all over Europe, and it’s clear that competent authorities in Member States do not have sufficient understanding about the use of botanicals
If you reside in the UK, you are still legally entitled to source butterbur from outside the country for personal use while it remains off a banned list. It’s sad to undermine the UK herbal industry in this way, but many people have used butterbur safely for centuries, and should continue to be able to do so within normal, safe, doses. Send a message to the authorities that we won’t be bullied in this way – and keep buying your butterbur!
Refer to a professional herbal practitioner for more detailed information on butterbur
Use our comment facility to share your stories and experiences of using butterbur
References
[1] Anderson N et al. Toxicogenomics applied to cultures of human hepatocytes enabled an identification of novel Petasites hybridus extracts for the treatment of migraine with improved hepatobiliary safety. Toxicol Sci 2009;112:507–20.

Yes, it is likely that one or possibly more companies make safe butterbur products, although we cannot be sure that all products that claim to be PA-free are indeed PA-free because they are not regulated by the FDA. Considering that many consumers will often opt for the cheapest brand, this can expose many people to serious liver and other problems. In my opinion, we should follow the example of Germany, Switzerland, and the UK and ban all butterbur products. Yes, some people will be deprived of an effective herbal treatment, but others will be spared life-threatening liver or fetal damage. We do have other herbal products, such as feverfew and boswellia, which can be very effective without the risk of serious complications.

This article is too general explaining the hazards of butterbur consumption. Just because those particular companies don’t make them without the harmful toxins doesn’t mean other companies don’t sell safe butterbur. I’ll copy and paste from WebMD so you have an exact, reliable source rather then me trying to explain it. “Butterbur is an herb. People use the leaf, root, and bulb to make medicine. Some butterbur preparations contain chemicals called pyrrolizidine alkaloids (PAs), which can damage the liver and cause other serious harm. Only butterbur products that are certified and labeled “PA-free” should be used.” -WebMD. So butterbur doesn’t need to avoided but the consumer must read into which sources eliminate the harmful toxin. Hope this helps clarify what this article should have said. -Cheers!

The safety of butter product remains controversial, but at least three countries have banned sales of all butterbur products – Germany, Switzerland, and the UK. Instead of butterbur I recommend trying boswellia and feverfew.

So according to your article, are you saying that the Petadolex brand butterbur is not a safe product to take anymore? I have read so much about Butterbur for migraines and have taken this supplement off and on for over three years. It helps me and I was a little concerned when I read your article. According to many other sources over the years, this company was the ONLY company that you should buy it from. Thank you!

I have suffered Migraine headaches for years but last year has by far been the worse one ever. I saw a Dr. in Arizona had some infuson Therapy the Headache went away for 3 months. The headache returned after 3 months then I was given steroids and that took care of the headache, but the side effects were not fun. Then I changed my lifestyle, I stopped eating all meat and dairy, excercising and I felt really good. However the headaches have returned and I have had the headaches now about a month and a half. Imitrex no longer works I am not taking any other medications, I went to the Neurologist he gave me a nerve block, I felt relief for a day but not 100%. He also gave me the Petadolex, I took one so far but after reading all of this and the side effects, it scares me. Any suggestions?

It looks like Source Naturals are using the original German product, but they do not specify if it is the original manufacturer, Weber & Weber.

Hi guys.. so would you say the source naturals is safe… Produced in Germany ?

I find this odd – I’ve had migraines for years and use on average one Frova tablet every two days (in clusters, the number of pills ingested works out to that average). I was so sick and tired of it all, so I did some research and decided to try Butterbur. That was two weeks ago, and I haven’t had one since. It can’t be a placebo effect, as I always expected Frova to do the same, but it only worked short term

PS, I would also strongly suggest that you pick up three books by Suzy Cohen, they are ‘The 24 Hour Pharmacist’, ‘Drug Muggers’ and one of her latest books ‘Headache Free’! She is a wonderful person who cares about people, and her books are an eyeopener and highly educational and entertaining! She has been a pharmacist for over 20 years and she is extremely concerned about the many dangers of pharmaceuticals! You can order these books on Amazon.com if you like!

And who controls the FDA? Big Pharma of course! They would rather see people take their dangerous drugs, with all of those horrendous side effects; like coumadin / warfarin for example, which contains rat poison as one of their ingredients; that’s right, rat poison! The side effects almost always leads to osteoporosis, also can cause Alzeimers and eventually damage the heart, liver, and kidneys! big Pharma would have no qualms about keeping you on dangerous drugs like this, for the rest of you life, rather than to take safe and effective supplements! Why aren’t supplements regulated? It’s very simple! The pharmaceutical industry is a multi-billion dollar per year monopoly! Do you think that they really want anyone else slicing in on their massive pie? Of course not! That is why they try so hard to get supplements off of the shelves by giving them a “black eye” and making such bogus claims about their safety!, the kettle calling the pot black so to speak! They also have the physicians in their hip pockets too! They pressure them into giving these many drugs to their patients (even if they really might not need them), by offering paid vacations, expensive dinners at exclusive restaurants and many other perks! Yes, Big Pharma is another huge industry that reeks with corruption today! They were originally there to help people who were sick, today they are compounding peoples illness by over prescribing them with drugs! We, as consumers need to be much more vigilant than ever! Don’t let any doctor pressure you into taking any drugs that you don’t feel comfortable taking! Read up on these drugs first, and see what the risks and side effects are! Also, by all means. explore the natural route! There are more and more doctors starting to practice alternative medicine, because they care about their patients, and they know of the many dangers of pharmaceutical drugs! They will only use them as a last resort. They will encourage and recommend good, safe supplements and herbs that will not only treat symptoms but also the cause!

Yes, I agree that butterbur works for many migraine sufferers – I am one of the authors of the pivotal study that proved its efficacy. And for most people who take the brand made in Germany the risks are low, especially if they do what you do – take a break after 3 months.

I am still going to take Petadolex. I’ve suffered from migraine with aura since I was 18 years old and am now 60. I’ve tired many, many pharmaceuticals over the years and “ONLY” Petadolex works !!!!! I take it for about 3 months and stop for about 3 months. When the migraines return, I go back to the Petadolex. IT WORKS. I’ve been doing this for a period of about 5 years now and have no indication of any negative side effects.

You may want to ask your NP for a different triptan, such as Maxalt (rizatriptan), which is going generic soon, or Zomig (zolmitriptan), Relpax (eletriptan), or any of the triptan family migraine drugs. Feverfew and Boaswellia are two very safe herbal products that can help along with magnesium and CoQ10. If your headaches are very frequent Botox is a good option.

I am so confused. I had asked my NP for Percocet to help with my migraines because the Imitrex doesn’t cut it. I cannot take any anti-inflammatories because of a blood disorder (or at least I shouldn’t). I have been because the Imitrex and Tylenol combination doesn’t help. I was hoping for something to give me some relief. My NP just went to a migraine convention in Chicago and they were recommending butterbur by weber and weber. I haven’t bought it yet. She also recommended Magnesium supplement, which I am taking. I was just looking up the butterbur and found this. Now I don’t know what to do.

You can read about them here on our website or you can buy one of my two books. http://www.nyheadache.com/index.php?option=com_content&view=article&id=27&Itemid=69
The electronic version of my book “The Headache Alternative: A Neurologist’s Guide to Drug-Free Relief” is available free with the download of our free iPhone app Migralex Headache Relief Diary.

Dear Dr Mauskop,
you wrote : “We have many other alternatives for the treatment of migraine headaches”. My daughter (15 years) has migraine every week. Can you pls advise any alternative treatment ? Thank you.

I was devastated to read this about Petadolex because I’ve been using it and finding it beneficial. Nevertheless, I appreciate your making these safety concerns known. I hope you’ll keep us updated here if anything changes regarding the known safety of the Weber & Weber product. Thank you.

Thank you, Paul. I agree with you – I would still not use any butterbur product, including the one from Weber & Weber. If the German or British government approves it, I will start recommending it again. We have many other alternatives for the treatment of migraine headaches, so it is not worth the risk of liver damage or other serious side effects.

Wanted to comment on statement below:

Volker Gallichio Says:
August 13th, 2012 at 12:01 pm
In 1978, Weber & Weber used methylene chloride as the extraction solvent for the
manufacturing of the active ingredient found in Petadolex. However, the
solvent was changed to a superior CO2 solvent in 1988 which did not change
the active ingredient or nature of the Petadolex ingredient.
——————-

My two cents-In 2009, the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, U.S Department of Health and Human Services (whew!) created a review document (pdf available at http://ntp.niehs.nih.gov/ntp/noms/support_docs/butterbur_nov2009.pdf)

In this review, “Chemical Information Review Document for Butterbur (Petasites hybridus, ext.” [CAS No. 90082-63-6], the process described by Weber & Weber is supported (from section 3):

“Current processing methods of P. hybridus typically include extraction of the aerial parts or rhizomes. Extraction of butterbur rhizomes using liquid CO2 under increased pressure yields extracts that contain PAs below the detection limit (0.1 ppm) (Danesch and Rittinghausen, 2003 [PMID:12864764]; Kalin, 2002).”

Still, I’m not using petadolex for now…but perhaps the “change” in W&W purification process is not as great a concern–as is apparently not allowing more PA’s to slip through.

UK warning:

The MHRA has recently become aware that unlicensed herbal products containing butterbur (Petasites hybridus) are being marketed in the UK and is warning consumers about the risks associated with the use of these products. Butterbur contains pyrrolizidine alkaloids (PAs) which studies have shown can result in serious liver damage and organ failure. PAs have also been shown to lead to cancer in animals. Butterbur is most commonly used to treat migraine and hayfever.

Butterbur products have been associated with cases of liver toxicity; 40 cases have been reported in the literature. Of these cases, nine were of acute hepatitis and two of the nine cases resulted in liver failure requiring transplantation. The cases of liver toxicity appear to have occurred with extracts of butterbur where the PAs had been removed and only small amounts remained. There is some evidence that other constituents found in butterbur such as the sesquiterpene constituents for example petasin may be implicated in the liver toxicity.

Due to the serious risks posed to individual patient’s health, the MHRA is advising anyone using products containing butterbur to stop doing so immediately and if they have any concerns they should seek the advice of their GP or pharmacist.

I thought it would be useful to share this –from UK Daily Mail, Feb 2012–it breaks my heart (and my head) to find this is no longer safe–it did help me a bit…but not enough to lose a liver and/or get cancer. Take care fellow Migraineurs!

Experts warn herbal remedy butterbur can cause liver damage and even organ failure
By LAUREN PAXMAN
UPDATED: 11:29 EST, 1 February 2012

Dangerous remedy: No products containing butterbur (pictured) have been sanctioned for use in Britain, but they are still being advertised here
Most of us see herbal remedies as a safe way to medicate, with few side effects.
But if they contain an unlicensed ingredient called butterbur, they could cause serious liver damage or even organ failure, experts have warned.
The Medicines and Healthcare products Regulatory Agency (MHRA) has urged British herbal shops to remove products containing butterbur – also called Petasites hybridus – from their shelves.
Butterbur is normally used to treat migraines, but it contains pyrrolizidine alkaloids, which studies have shown can cause serious liver damage and organ failure.
Currently, no products containing the ingredient have been sanctioned for use in Britain under the Traditional Herbal Registration Scheme. Several other European countries have also banned it.
However, the MHRA said products containing butterbur are currently being marketed in the UK. And while no adverse reactions to it have been reported here, cases of liver toxicity have been reported elsewhere in Europe.

You are right, we do not know if any butterbur product is safe. The only way we will know if the manufacturers conduct the required tests.

Sounds like an ” I don’t really know” answer. Is it anymore dangerous than axert or flexeril? How will we know for sure?

Dear Dr. Mauskop,

The FDA has been diligently enforcing their final cGMP rules by physically auditing all herbal supplement manufactures not in compliance and filing form # 483 notices. Hundreds of herbal manufactures have already received 483’s by FDA inspectors and are in the process of complying with FDA:
http://www.fda.gov/Food/DietarySupplements/GuidanceComplianceRegulatoryInformation/RegulationsLaws/ucm110858.htm

Of course by importing butterbur products from Germany only Petadolex has ever been subjected to FDA’s physical audit prior to being released for sale in the USA.

You may also be interested in knowing, the University of Mississippi school of Pharmacy recently published results of all commercially available butterbur products and found that only Weber & Weber’s products from Germany contained no PA’s while providing the highest level of active ingredients.
http://www.ncbi.nlm.nih.gov/pubmed/22809670

I believe with confidence you can recommend and / or dispense Petadolex to your prophylactic migraine patients.

Unfortunately, our FDA does not regulate herbal products and as you pointed out many butterbur products on the market could be ineffective at best or toxic at worst. The product made by your company may be in fact safe, but lack of endorsement by the German government makes it difficult to judge the purity of your product as well. This is why we still would not recommend any butterbur products to our patients.

In 1978, Weber & Weber used methylene chloride as the extraction solvent for the
manufacturing of the active ingredient found in Petadolex. However, the
solvent was changed to a superior CO2 solvent in 1988 which did not change
the active ingredient or nature of the Petadolex ingredient. In addition,
the CO2 method has a secondary benefit of selective depletion of toxic
pyrrolizidine alkaloids.

Unfortunately, the review process by the German health authority BfArM
regarding the original extract application of 1978 took decades, and as a
result the health agency declared the changes of extraction solvent
marketed after 1988 to be different than the application submitted in
1978, even though all analytical test methods employed demonstrated
identical results. There is no difference in the active ingredients of the
extract whether methylene chloride or CO2 is used as the solvent since.

What’s important, all clinical studies published had been performed with
the unique and patented CO2 Petadolex extract manufactured by Weber &
Weber since 1988. Many different butterbur products are sold in the USA.
Those that are not labeled “Petadolex” use different ingredients and most
of them do not contain the labeled amount of petasins or no petasins at
all, some even contain toxic pyrrolizidine alkaloids. Products labeled
“Petadolex” contain the only extract that was used in published randomized
controlled clinical trials for migraine prevention and shown to be safe
and effective.

I am somewhat relieved to read this. being a medical and consumer health journalist/writer, I am often sent products for review. Once, a box full of Petadolex arrived. Although I get migraines every other day, and have tried everything to thwart them, every time I picked up this product, I put it down again, as I just didn’t want to take the low-probability risk of liver disease.