ABSTRACT
Mequitazine is a potent, non-sedative, long-acting H1-specific antihistamine proven to be a better therapeutic drug than other conventional antihistamines. It is also reported by many authors that the drug produces less sedative or other depressive actions on the central nervous system than other antihistamines. In order to evaluate the advantage of this drug in Asian people, an assessment of side effects of mequitazine, in comparison with chlorpheniramine, on the central nervous system was done in 20 healthy Thai volunteers, 10 males and 10 females 23-39 years of age, using a double blind crossover placebo controlled trial. Various subjective tests: alertness scale rating, visual analogue scale rating as well as objective tests: card sorting, glassbead picking and estimation of reaction time, were performed. There were no significant differences in side effects on the central nervous system between mequitazine and the placebo, whereas chlorpheniramine did produce side effects.