2005-05-13
American Botanical Council, Heather S. Oliff, PhD

Migraines occur in an estimated 3% to 7% of all children. Because most migraine therapies seem to be ineffective in children, there is a strong need for further research on migraine prevention in children. Numerous studies have evaluated therapies for adults with migraines; however, only a few controlled trials have investigated the prophylactic treatment of migraines in either children or adolescents.

Butterbur (Petasites hybridus), a native European plant, is used in conditions like migraine, asthma, urinary tract spasms, and back pain. The active components are thought to be sesquiterpenes. The purpose of this open-label study was to determine the safety and efficacy of a standardized butterbur extract in the prevention of migraines in children and adolescents.

Because approval of placebo-controlled trials in children is difficult to obtain from an ethical review board in Germany, an open-label study was performed. A total of 108 children (n = 29 [6-9 years]) and adolescents (n = 79 [10-17 years]) were enrolled in a multicenter prospective, open-label study. Only patients suffering from migraines for at least 1 year were included in the trial. Patients were treated with 50 to 150 mg of special butterbur root extract (Petadolex®, Weber and Weber GmbH & Co, KG, Germany) for 4 months. The dose of the butterbur was dependent on the subjects' age and tolerance of the medication. Treatment progression was recorded in migraine journals especially designed for children and adolescents.

The number of migraine attacks in children and adolescents were substantially reduced by the butterbur root extract. Of all patients, 77% reported a reduction in the frequency of migraine attacks by at least half. Ninety-one percent of patients reportedly felt substantially or at least slightly improved after 4 months of butterbur treatment. The butterbur extract was very well tolerated with few adverse events. Belching was the most commonly reported adverse effect and is the only significant and well-known side effect of the standardized butterbur extract. All other adverse events were mild and did not lead to premature termination of the study.

The results of this study indicated that butterbur root extract may be an effective and well-tolerated prophylactic treatment of migraines in children and adolescents. Furthermore, the data reported here confirm the results found in other clinical studies and drug-monitoring trials in adults. (For an example of a recently published randomized controlled trial in adults in which Petadolex successfully lowered the frequency of migraines, see Lipton et al 2004 in Neurology1, HC 020251.276.) The authors caution that although the design of this study alone was not sufficient to draw any definite conclusions regarding effectiveness of butterbur, these results together with the available randomized trial data demonstrate that butterbur extract seems to be an effective alternative for prophylactic migraine treatment also in children and adolescents. They suggested that the results warrant a placebo-controlled trial in children and adolescents to further document butterbur's efficacy in migraine prevention of this patient group. Overall, the results of this study with a natural product are promising for young patients affected by migraines.

Note: the standardized butterbur root extract used in this trial (Petadolex®) was purified to remove all naturally occurring pyrrolizidine alkaloids (PAs) according to the German pharmaceutical requirements. Various types of PAs are known hepatotoxins and the use of unpurified extracts containing PAs might cause liver damage or, according to these authors, liver cancer.