Hundreds of care homes are still regularly using a “chemical cosh” of powerful drugs to quieten difficult dementia patients, despite a national review into the practice, a new report suggests.

A study from five universities found no overall reduction in the prescribing of antipsychotics in UK care homes between 2009 and 2012, three years after the Government launched the National Dementia Strategy.

In 2012, 77 per cent of treatments using the drugs were described as “excessive” and lasting for longer than the recommended six weeks, the report found.