Auditory P300 after Taking Hypnotic Zolpidem

Original Article

Psychiatry Investigation 2007;4(1):22-6.

Kyoung-Uk Lee, MD1;E-Jin Park, MD2;Chin-Yang Kang, PhD3;Sang-Ick Han, MD2;Kweon-Haeng Lee, MD4; and Yang-Whan Jeon, MD2;

¹;Department of Psychiatry, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, ²;Department of Psychiatry, Our Lady of Mercy Hospital, The Catholic University of Korea College of Medicine, Incheon, ³;College o

Abstract

Objective

:
Although the hypnotic, zolpidem, is known to be free of any detrimental residual effects, its residual effects on cognitive function after its elimination half-life have not been sufficiently investigated. This study was designed to examine the residual effects of zolpidem on cognitive function using event-related potentials (ERPs).

Methods

Twelve healthy right-handed men participated in this study. ERP recordings were conducted at baseline and 5 hours after taking 10 mg of zolpidem. The auditory oddball task included the presentation of a series of standard (1,000 Hz, 75 dB, 80%) and target tones (2,000 Hz, 75 dB, 20%) in a predetermined quasi-random order. The data were analyzed using analysis of variance (ANOVA).

Results

On the behavioral task, the reaction time was significantly delayed in the post-drug condition compared to the baseline. The P300 amplitude was significantly decreased in the post-drug condition compared to the baseline. However, the P300 latency showed no difference between the pre- and post-drug conditions.

Conclusions

The residual effects of zolpidem on cognitive function may persist after its elimination half-life. Further large placebo-controlled trials are needed to confirm the findings of this study.

Key words Hypnotic;Zolpidem;Sleep;Residual effect;Event-related potentials;P300.