Banisteriopsis caapi, a Forgotten Potential Therapy for Parkinson’s Disease?

Introduction

The paper reviews the history, pharmacology, and clinical evidence for harmine-containing preparations derived from Banisteriopsis caapi and Peganum harmala as potential therapies for parkinsonism. Earlier research from the 1920s and 1930s identified harmine (also called banisterine, telepathine or yag eine) as the active alkaloid in both plants, and early investigators reported rapid but variable improvements in motor function after parenteral administration. Interest waned with the advent of other agents considered more predictable or effective, and because oral preparations were thought to have limited efficacy. Djamshidian and colleagues set out to summarise the early clinical trials and case series, to outline the known pharmacology of harmine, and to reconsider whether harmine or B. caapi extracts merit renewed investigation for Parkinson's disease (PD). The review also situates harmine among other monoamine oxidase (MAO) inhibitors and discusses safety signals that influenced its historical abandonment, while noting more recent preclinical and small clinical data that suggest mechanisms relevant to PD and a rationale for further controlled trials.