© Agnieszka Kwiecień, Nova (Wikimedia Commons) · CC BY-SA 4.0 · Commons
Butterbur
Caution🐾Gewöhnliche Pestwurz · (Petasites hybridus)
Daisy family (Asteraceae)
Description
Butterbur is a daisy-family perennial of damp banks and floodplains that unfurls strikingly large leaves in spring. Medicinally the rhizome is used — but only in the form of PA-free, standardised commercial preparations. Its active constituents are petasin and isopetasin, credited with antispasmodic properties; standardised extracts are studied for migraine prevention. The raw plant, however, contains liver-damaging pyrrolizidine alkaloids and must not be processed at home or used as a tea.
Standardized root extracts (standardized to petasins) reduce the frequency and intensity of migraine attacks in controlled trials. Use only PA-free, quality-controlled products – never the raw plant.
Sources: [3]
Standardized leaf or root extracts can ease symptoms of allergic rhinitis (hay fever). Only PA-free, standardized preparations are suitable for this.
Sources: [2]
Traditionally, butterbur preparations are used as antispasmodics for gastrointestinal and urinary-tract spasms. Here too, only PA-free, standardized products should be used.
Sources: [1]
The raw plant contains hepatotoxic pyrrolizidine alkaloids; use only PA-free, standardized products; not during pregnancy or breastfeeding. Possible allergy in people sensitive to the daisy family.
Harvested part: rhizome/root (for standardized extracts)
- PetasinSesquiterpene
Main active compound; antispasmodic and anti-inflammatory, the marker substance of standardized extracts.
- IsopetasinSesquiterpene
Closely related sesquiterpene with similar antispasmodic activity.
- Pyrrolizidin-Alkaloide (z. B. Senecionin)Alkaloid
Hepatotoxic and potentially carcinogenic; must be practically removed in quality-controlled products.
- FlavonoideFlavonoid
Contribute to antioxidant and anti-inflammatory effects.
- [3]MonographPetasites for Migraine Prevention: Mode of Action, Pharmacology and Safety (Frontiers in Neurology, 2022)(accessed: 2026-06-24)
- [1]WikipediaGewöhnliche Pestwurz – Wikipedia(accessed: 2026-06-24)
- [2]WikipediaPetasites hybridus – Wikipedia(accessed: 2026-06-24)