Butterbur and new migraine guidelines

The American Academy of Neurology and the American Headache Society just updated their guidelines for migraine prevention. In addition to adding another beta blocker to their first-line (A list) of preventative drugs showing firm evidence of effectiveness such as the anti-epileptics, for the first time they added a supplement to the A list, butterbur. Here's part of the discussion in MedScape:

Dr. Wilner: I am astonished that there is level A evidence for this herb. This might be the first instance in the world that there is level A evidence for a supplement, because supplements by their very nature are not controlled, in terms of their potency. They come from different manufacturers, and usually no sponsor is willing to put in the effort to do a double-blind, randomized study to get level A evidence. How did butterbur, which is a plant, end up with level A evidence?

Dr. Dodick: Butterbur is a plant extract. Three placebo-controlled studies have been conducted with butterbur. My hat is off to the investigators who took it upon themselves to get support necessary to conduct the studies. That shows you the pioneering spirit of some of these neurologists in headache medicine who strive to provide the best evidence possible. It looks to be, at least according to the data, as effective as the more conventional prescription medications that we use.

Dr. Wilner: I have 3 questions about butterbur. How do we know how much to take? Do we know the active ingredient? What side effects should be anticipated?

Dr. Dodick: The active ingredients are petasin and isopetasin, which appear to have anti-inflammatory properties. It can be ordered online or purchased at health food stores. Sometimes pharmacies will carry it and you can get it off the shelf. Generally, it is dosed twice or 3 times daily, usually 75 mg.

Dr. Wilner: Is it a tea, a drink, or a capsule?

Dr. Dodick: It is a capsule. Most of the side effects are gastrointestinal. It can cause dyspepsia, bloating, or diarrhea, but generally it is well tolerated.

In a headache specialist's hands, butterbur is used mainly as adjunctive therapy. We use it in addition to conventional prophylactic or preventive medication that we select. As an adjunctive therapy, it can be useful.

I have used it in children. Parents, in particular, don't want their children taking prescription medication, but they are more than happy to have their child take a supplement, so I have used it effectively and successfully in children.
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I just started butterbur and you do need to be careful about which brand you buy.......the one that is used in research is a butterbur formulation called petadolex that is manufactured by enzymatic therapy (among others). The butterbur formulation needs to be free of pyrrolizidine alkaloids which can cause liver damage. I am starting on a low dose at 50mg though the American Academy of Neurology states that an effective dose is 75mg twice a day.

I did try Petrodolax, but ended up with major diarrhea that would not quit, so I had to discontinue it. I was really disappointed as I had really hoped it would work for me. But I'd definitely give it a try if you have not.