A questionnaire was sent to all GPs (n=107) in West Lincolnshire PCT to investigate the perceived advantages and disadvantages of benzodiazepines and Z-drugs. The response rate was high at 78.5%, statistical analysis of the responses to individual questions revealed the following:
Responders perceived that Z-drugs were more effective than benzodiazepines in terms of:
- patients feeling rested on waking (p < 0.001)
- daytime functioning (p < 0.001)
- total sleep time (p = 0.03)
Responders also perceived that Z-drugs were safer in terms of:
- tolerance (p < 0.001)
- addiction (p < 0.001)
- dependence (p < 0.001)
- daytime sleepiness (p < 0.001)
- road traffic accidents (p = 0.018)
- use in older people (p < 0.001)
The article concludes that, "GPs' beliefs about effectiveness and safety are not determined by current evidence or national (NICE) guidance" and suggests that this may be a reason for the increase in prescribing of Z-drugs in comparison to benzodiazepines.
The NICE guidance for Z-drugs recommends that non-medicine treatments are first-line. Short courses of hypnotics can be prescribed to treat severe insomnia that is interfering with normal daily life. It is also noted that there is no firm evidence of differences between short acting benzodiazepines and Z-drugs and as such the cheapest drug, taking into account the dose and cost per dose, should be prescribed. Finally, the NICE guidance recommends that there is no reason to change agent based upon lack of efficacy.
Action: Prescribing of all hypnotic drugs should be restricted to short term treatment in severe cases of insomnia. Z-drugs should not be used in preference to short acting benzodiazepines.