The Effects of Single and Repeated Administration of Ebastine on Cognition and Psychomotor Performance in Comparison to Triprolidine and Placebo in Healthy Volunteers

Summary

Objective:The cognitive and psychomotor effects of 10 mg, 20 mg and 30 mg ebastine, a second generation H1-receptor antagonist, were compared with sustained release triprolidine 10mg (as averum) and placebo in 10 healthy volunteers in a double-blind, randomised crossover study.

Methods: Following each dose, subjects were required to perform a series of tests of cognitive function and psychomotor performance at 1 h, 2 h, 4 h and 8 h post-dose on days 1 and 5. The test battery consisted of critical flicker fusion, choice reaction time, simulated car tracking task, Sternberg memory scanning task, assessment of subjective sedation (LARS) and subjective evaluation of sleep (LSEQ).

Results: Ebastine at all doses investigated was not statistically significant from placebo in any of the objective tests used. However, as expected for a positive internal control, a number of objective measures were significantly disrupted by triprolidine (p < 0.05). Triprolidine produced an overall increase of the peripheral reaction time component of the simulated car tracking task (SCTT), the I difference with placebo reaching statistical significance on day 1,8 h post-dose (p < 0.05). The mean tracking accuracy scores were also significantly impaired following the administration of triprolidine after 8 h on day 1 (p < 0.05). Triprolidine also produced a clear decrement on the SMST (Sternberg Memory Scanning Task), which was significantly different from placebo, at 4 h and 8 h post-dose on day 1. Subjective reports of sedation (LARS) were significantly greater at 2 h and 4 h following triprolidine administration on day 1 and ebastine (30 mg) was rated as sedative 4 h following administration on day 5. The perceived sedative activity of ebastine 30 mg was also reflected in the subjective reports on the LSEQ on day 1 (p < 0.05).

Conclusions: These results allow the conclusion that ebastine, at its recommended therapeutic doses of 10–20 mg, is demonstrably free from impairment on objective aspects of psychomotor and cognitive function in a study where the psychometric assessments were shown to be sensitive to disruptive effects, as evidenced by the action of the positive control, triprolidine 10 mg.

Key Words::

• Antihistamines
• Ebastine
• Cognition
• Psychomotor performance
• Sedation
• Triprolidine