The effects of single and repeated doses of oral scopolamine, cinnarizine, and placebo upon psychological performance and physiological functioning

✍ Scribed by Dr. A. C. Parrott; Dr. J. F. Golding; R. J. Pethybridge

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 680 KB
• Volume: 5
• Category: Article
• ISSN: 0885-6222
• DOI: 10.1002/hup.470050305

✦ Synopsis

Abstract

The present study was one in a series in the Institute of Naval Medicine's Motion Illness Project. A battery of psychological performance tests (producing 26 indices of mental and hand‐‐eye co‐ordination), together with visual near fixation point, resting heart rate and a self‐rated feeling state questionnaire, were used to compare the effects of thrice‐daily oral doses of scopolamine (0.6 mg), cinnarizine (30 mg) and a lactose placebo in a double‐blind crossover trial on 12 healthy male volunteers. Measurements were made 1–2 and 5–6 h after the initial dose, then the next day following the last successive dose (1–2 and 5–6 h after the fourth dose; or 25–26 and 29–30 h after the initial dose). Scopolamine demonstrated clear physiological effects, with reduced heart rate from the first oral dose onwards, and visual near‐point values increasingly distant over successive doeses. Cinnarizine did not produce significant physiological changes. Neither drug produced significant effects on subjective mood. Significant ANOVA drug effects or drug × time interaction effects were present with five out of the 26 performance variables: logical reasoning error, memory word‐recall errors; continuous four choice reaction time; concept identification time; SERS task commission error. However only two of these (memory error, four choice reaction time) demonstrated patterns of effect which were considered to be attributable to the drugs. Both cinnarizine and scopolamine impaired memory error and four choice reaction time. Only for visual near‐point with scopolamine was there evidence that repeated dosing led to increasing physiological/mental performance effects.