Phenothiazine-Produced Extra-Pyramidal System Disturbance

Introduction  When Delay and Deniker introduced chlorpromazine in 1952, they described sideeffects which simulated post-encephalitic parkinsonism. It has since been demonstrated that these signs of extra-pyramidal system disturbance (SESD) are a feature of all anti-psychotic chemotherapeutic agents. There is, however, no general agreement among clinicians as to the therapeutic role of SESD. Some consider these symptoms undesirable and seek compounds in which they are minimal, while others believe their presence indicates adequate medication and are a sine qua non for improvement. These irreconciliable attitudes are caused in large measure by the lack of standardized methods for measuring and reporting SESD. Haase,¹ for instance, studied fine muscular movements as evidenced in handwriting, while Denber² reports on gross rigidity in certain muscle groups.Recurrent questions that arise include: How long does it take for the signs to appear? How long do they