Comment on: "Phytomedicines in the Treatment of Migraine"/Reply

[...]the National Center for Natural Products Research has detected pyrrolizidine alkaloid at levels between 0.1 and 4.48 |ig per tablet, capsule or gel content in 7 out of 21 tested products; one product was a liquid with a high content of 8.43 |ig pyrrolizidine alkaloids per mL [3]. The authors' concern regarding butterbur safety stems not from a lack of awareness regarding the proprietary method by which Petadolex® removes pyrrolizidine alkaloids (which unfortunately are not available to the general public for review), but rather from a concern about the capacity of the individual patient and front-line healthcare practitioner to differentiate 'Petadolex®' from the number of 'butterbur' compounds that exist in the North American and international markets. Thilinie Rajapakse Thilinie.Rajapakse @ albertahealthservices.ca 1 Division of Neurology, Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada 2 Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada 3 Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada 4 Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada 5 Women and Children's Research Institute, Edmonton, AB, Canada