Complex Cognitive Performance and Antihistamine Use (Executive Summary)

Research has demonstrated that the majority of antihistamines H1 antagonists have sedative effects and can impair psychomotor performance however, it is claimed that astemizole hismanal does not possess central nervous system side effects. A two-factor, repeated measures, double-blind design was used to compare the effects of three treatments two antihistamines and one placebo on cognitive information processing, mood, selected physiological measures, subjective feelings of drowsiness, and subjective performance ratings in 28 healthy men. Evaluations were given at 1,3,5,7,9,11, 13, and 15 hours post ingestion. Time-of-day effects were evident in following directions, unstable tracking, code substitution, serial additionsubtraction, logical reasoning, manikin, and pattern comparison tasks. A general trend of improved scores through the day was observed and a temporal pattern of a low performance was suggested in the afternoon 200 pm and 400 pm. Temporal effects were noted for physiological measures. Keywords Cognitive performance, Visual motor performance, Mood scales, Antihistamine.