Petadolex Pro-Active. Butterbur is a shrub that grows in Europe and in parts of Asia & North America, typically in wet, marshy ground or on sandbars near streams. The generic name petasites is derived from the Greek word petasus , a type of broad-brimmed hat worn by shepherds, referring to the broad, downy leaves. The name, butterbur, is attributed to the traditional use of its large leaves to wrap butter in warm weather. Butterbur (Petasites hybridus) has exotic stalks of purple flowers that bloom before its elephantine leaves appear. Older specimens lose all their flowers and the leaves grow enormously, up to 2 feet across. Butterburs are characterized chiefly by their inflorescence (the arrangement of the blossoms), which is the most telling feature of the plant. It is unique in that it flowers prior to the emergence of its leaves, and at first glance resembles a strange seeming hybridisation of broccoli and kale. Enzymatic Therapy's Petadolex Pro-Active supplement contains pure butterbur extract to support healthy blood vessel tone in the head.* The patented method of extraction for Petadolex Pro-Active ensures the valuable petasites compounds are captured, while leaving out toxic levels of inherent compounds such as pyrrolizidine alkaloids (PAs). This product is tested for pyrrolizidine alkaloids, made possible by using this patented process (U.S. Patent #6,551,626). Research shows Petadolex can reduce occurrences with continuous use. For decades, Petadolex has been recommended in Europe, and has been available in the United States, from Enzymatic Therapy, since 2002. Contains no sugar, salt, yeast, wheat, gluten, corn, soy, dairy products, artificial flavoring, or preservatives. Recommendations: Take 1 softgel three times daily for the first four weeks. Thereafter, 1 softgel twice daily, or as recommended by your healthcare professional. Petadolex Pro-Active is distributed by Enzymatic Therapy under license from Weber & Weber. Product of Germany.