Hypnotics in insomnia: the experience of zolpidem

One of the most commonly prescribed medications to treat insomnia is zolpidem, a nonbenzodiazepine compound that is available as an immediate-release oral tablet formulation, an extended-release oral formulation, an oral spray formulation, and as sublingual formulations. The purpose of this review was to summarize the data currently available on the efficacy and safety of zolpidem in the treatment of insomnia among adults.

Published studies on the use of zolpidem in the treatment of insomnia were identified by using combinations of relevant search terms in PubMed and Google Scholar. Studies were included if they were placebo- or active comparator-controlled studies, with the exception of trials on the long-term use of zolpidem. Studies were limited to those conducted in adults. Studies were not included if the patient population was small, if the study was not designed or powered to assess the efficacy or safety of zolpidem, if insomniac patients had a medical condition in addition to insomnia (with the exception of comorbid depression or anxiety for studies on comorbid insomnia), or if zolpidem was given concomitantly with any other therapy (with the exception of selective serotonin reuptake inhibitors for studies on comorbid insomnia).

Twenty-five studies designed to evaluate the efficacy of zolpidem in insomnia and 51 studies reporting the safety of zolpidem in insomnia were included in this review.

The studies discussed in this review report the efficacy and safety of zolpidem in both young adults and the elderly. It can be used for either bedtime or middle-of-the-night administration, over the short or long term, with minimal risk of withdrawal or abuse. The use of zolpidem is associated with rebound insomnia, complex sleep-related behaviors, and next-day residual effects (after middle-of-the-night dosing) on driving ability, memory, and psychomotor performance.