Taking sleeping pills frequently can increase the risk of premature death more than five-fold a new study has warned.

The study published in the British Medical Journal Open found that patients who even take fewer than 18 pills a year more likely to die early than those not on medication.

The higher the dose the greater the risk. And those on higher doses also have an increased risk of cancer said the researchers at the Jackson Hole Centre for Preventive Medicine in Wyoming and the Scripps Clinic Viterbi Family Sleep Centre in California.

The commonly prescribed drugs that may raise such

risks included benzodiazepines newer sedative hypnotics zolpidem zopiclone and zaleplon and barbiturates and antihistamines.

However experts said worried patients should not stop taking the pills but talk to their doctors first the Daily Mail reported.