Reserpine is one of the active alkaloids extracted from the root of the plant Rauwolfia Serpentina. The physiological changes resulting from the use of the drug in animals—such as hypotension, bradycardia, sedation, increased peristalsis, meiosis, etc.—are probably the result of a central action. The precise sites are not known although it seems likely that one of them is the midbrain reticular formation. There is no evidence of any peripheral action, nor of any direct effect on the cortex. The reason for the long latent period, before the drug begins to show an action is still obscure (Lancet Leader, 1955; Mover, 1955; Plummer et al., 1954). The recent work on the pharmacological relationships between Reserpine, Serotonin and the hallucinogens suggests interesting possibilities (Pletscher et al., 1955; Shore et al., 1955).

There is already a considerable literature on the toxic effects of Reserpine, the most serious of which are Parkinsonism, of a post-encephalitic type, and severe depression (Achor et al., 1955; Barsa and Kline, in press; Locket, 1955; Schroeder and Perry, 1955; Stead and Wing, 1955).