Educational reference, not medical advice. Talk to a clinician before changing what you take.Read more.

Remedy · herb

Butterbur

Also: Petasites hybridus

An effective migraine preventive whose raw form is liver-toxic — only PA-free extracts should ever be used.

Active compounds Petasin

Evidence by condition

Each grade reflects the research for Butterbur and that condition specifically.

Raw butterbur contains pyrrolizidine alkaloids that are toxic to the liver and potentially carcinogenic. The American Academy of Neurology withdrew its butterbur recommendation in 2015 over these safety concerns. Only certified PA-free extracts should ever be considered, and only with clinician oversight.