Petasites hybridus (Butterbur root) extract in the treatment of asthma--an open trial.

The efficacy and tolerability of a butterbur root extract (Petadolex) for the treatment of asthma was analyzed in a prospective, non-randomized, open trial. Subjects included 64 adults and 16 children/adolescents treated for two months with the extract, followed by two months during which the intake of the extract was optional. Concomitant asthma medication was permitted. The number, duration, and severity of asthma attacks decreased, while peak flow, forced expiratory volume (FEV1), and all measured symptoms improved during therapy. In addition, more than 40 percent of patients using asthma medications at baseline reduced intake of these medications by the end of the study. This study suggests the Petasites hybridus extract Petadolex is an effective and safe therapy for the treatment of asthma.