Banisterine and Parkinson's disease.

It is of historical interest that 63 years ago Louis Lewin reported the use of a hallucinogenic compound prepared from the South American vine, Banisteria Caapi, to treat Parkinson's disease (PD). This psychoactive compound, named banisterine, proved to be identical to harmine, but 30 years were to pass before it was shown to be a reversible monoamine oxidase (MAO) inhibitor. The first reports of the use of banisterine to treat postencephalitic parkinsonism in 1929 created a stir in the popular press and banisterine was hailed as a "magic drug." Despite continued studies of the harmala alkaloids by other researchers, interest in the therapeutic value of these compounds vanished during the 1930's. The story of banisterine is reviewed because it was the first MAO inhibitor to be used in parkinsonism, and illustrates the historical role of psychoactive drugs in the development of effective therapies, and in elucidating the pathophysiology of PD.