Hypnotic hazards and effects of z-drugs immeasurable
“It is difficult to know the extent of use and adverse effects of zolpidem and other z-drugs (zopiclone and zaleplon) because they have never been listed on the Australian Pharmaceutical Benefits Scheme, senior Sleep Disorders Physician Dr Les Olson writes in the latest edition of Australian Prescriber.
Following the media attention given to side effects in patients taking zolpidem, Dr Olson reviews the known adverse reactions of the z-drugs.
“Although the media have been impressed with the outlandish adverse events reported with zolpidem, these events are not unprecedented. Amnesia, hallucinations and bizarre behaviour were also seen frequently in patients taking the short-acting benzodiazepine, triazolam, for insomnia,” Dr Olson writes.
“All of the bizarre behaviours reported, such as sleep eating, sleep sex and sleep driving, are more likely to represent ‘wakeful behaviour with amnesia’ than behaviour while asleep.”
“Z-drugs have few advantages over benzodiazepines, and there is no good reason for their use in insomnia. It is possible to manage insomnia without ever using hypnotic drugs and this approach should be the rule rather than the exception.”
“If patients are prescribed z-drugs they should be made aware that sedation, confusion and disinhibition may occur. They should be advised to avoid alcohol, and the hypnotic should always be taken once the patient is in bed, not on the way to bed.”
“Evidence that z-drugs, especially zolpidem, commonly cause adverse effects, not predictable from their pharmacology, is weak. Zolpidem may cause hallucinations relatively frequently (as triazolam did), but reports of ‘abnormal behaviour with amnesia’ probably reflect predictable effects.”
Dr Olson says these adverse effects are not unique to z-drugs and could be limited by reduced prescribing.
“If there were fewer prescriptions for zolpidem and other z-drugs there would be fewer adverse events,” Dr Olson writes.
Non-medicine strategies for managing insomnia and guidance for counselling patients are available from the National Prescribing Service Limited (NPS) website www.nps.org.au.
For all hypnotics, NPS advises that doctors use the lowest dose for the shortest time possible (ideally for less than two weeks and no longer than four weeks) and re-evaluate within seven to 14 days of starting therapy.
For the complete article visit the Australian Prescriber website www.australianprescriber.com