Certain sleeping pills could be putting you to sleep for good, with those taking the drugs on a regular basis more than four times likely to suffer an early death, a US study has found.
Even those taking the pills only 18 times a year are more than 3.5 times as likely to die early as those prescribed none.
The study, published in the online journal BMJ Open, found those taking high doses of the commonly used pills faced a significantly increased risk of cancer.
The drugs included benzodiazepines, such as temazepam; non-benzodiazepines, such as zolpidem, eszopiclone, and zaleplon; barbiturates; and sedative antihistamines.
The study tracked the survival of 10,500 people who were prescribed a range of sleeping pills for an average of two-and-a-half years between 2002 and 2007.
Their survival was compared to more than 23,500 people, matched for age, sex, lifestyle factora and underlying health problems, but who had not been prescribed sleeping pills over the same period.
People who took up to 18 doses a year were more than 3.5 times as likely to die as those prescribed none, those taking between 18 and 132 doses were more than four times as likely to die, while people taking more than 132 doses a year were more than five times as likely to die as those prescribed none.
Those taking the highest doses were 35 percent more likely to develop a form a cancer.
The authors of the study said while showing association does not necessarily prove cause and effect, the research does back up previous research showing an increased risk of death among users of sleeping pills.
Lead author Dr Daniel Kripke, of the Scripps Clinic, told the British Medical Journal Open the "meagre benefits" of sleeping pills do not justify the "substantial risks".
"A consensus is developing that cognitive-behavioural therapy of chronic insomnia may be more successful than hypnotics."
BMJ Open editor in chief, Dr Trish Groves, agreed the findings raise further concern around the prescription drugs.
"Although the authors have not been able to prove that sleeping pills cause premature death, their analyses have ruled out a wide range of other possible causative factors. So these findings raise important concerns and questions about the safety of sedatives and sleeping pills."