Effects of topical administration of levocabastine on psychomotor and cognitive function.

The possible central nervous system effects of topical administration of levocabastine, a new H1-antagonist, were investigated in a double-blind, placebo-controlled, crossover study using a battery of objective and subjective tests. These were carried out in 12 volunteers up to five hours postapplication. Neither the recommended (0.5 mg/mL) nor the four times higher (2.0 mg/mL) concentration level was found to be distinguishable from placebo, while the verum (triprolidine 10 mg) was significantly worse, on both objective and subjective measures.