Pills for insomnia and anxiety 'are not candy' researchers have warned after finding the drugs are linked to an increased risk of dying.
Research has found that people taking the drugs are at least a third more likely to die during the 13-year study than those not on them.
One suggested reason for the effect is that sleeping pills and anti-anxiety drugs affect people's response times, alertness, and co-ordination.
This may make them more prone to falls and other accidents.
Another theory is that they interfere with the breathing system and affect any breathing problems as the person sleeps.
The medicines also work on the central nervous system, possibly increasing the risk of suicide.
Genevieve Belleville, from Laval University's School of Psychology in Canada, who led the study, said: "These medications aren't candy, and taking them is far from harmless.
"Given that cognitive behavioural therapies have shown good results in treating insomnia and anxiety, doctors should systematically discuss such therapies with their patients as an option.
"Combining a pharmacological approach in the short-term with psychological treatment is a promising strategy for reducing anxiety and promoting sleep."
The research, published in the Canadian Journal of Psychiatry, was based on data from more than 14,000 people between 1994 and 2007.
It was found those who took the drugs at least once in the month before the survey had a higher chance of dying from any cause.
The data includes information on people aged 18 to 102, surveyed every two years between 1994 and 2007.
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