In February 2008 the Therapeutic Goods Administration (TGA) imposed a boxed warning on the product information for medicines containing zolpidem. The warning alerts prescribers to the potentially dangerous, complex sleep-related behaviours that may be linked to zolpidem use. It also advises against using zolpidem with alcohol, that caution is needed with concurrent use of other CNS depressants, and to limit use to a maximum of 4 weeks.1

NPS has published a Position Statement on Zolpidem to explain the background to the safety change and to describe the current place of zolpidem in insomnia therapy.

If a sleep-related event occurs with zolpidem (or any other hypnotic), stop the medicine to avoid the potential harms to the patient and the community.

Non-drug therapies are recommended as initial treatment for insomnia. If a hypnotic is considered appropriate for short-term insomnia, use the lowest dose for the shortest time possible (ideally, less than 2 weeks) and re-evaluate within 7–14 days of starting therapy.

The evidence linking zolpidem with sleep-related behaviours consists of reports collected through postmarketing surveillance, particularly in Australia, and published case reports. Events reported with zolpidem have involved a variety of bizarre behaviours such as sleepwalking, sleep-eating and sleep-driving, with no subsequent memory of the event.2 Similar behaviours have been reported with other hypnotics3 and there is a warning to this effect in the product information of all hypnotics. However, the pattern of reports with zolpidem has been interpreted by the TGA as a signal of increased risk with this specific drug.2 A causal link with zolpidem and these behaviours has not been established and, while these behaviours are considered rare, the incidence is uncertain.

Sleep-related behaviours have occurred with therapeutic doses of zolpidem in people without any obvious predisposing factors.4 However, alcohol, concurrent use of other CNS depressants, or higher than recommended doses of zolpidem, probably increase the risk of these events.