Drug costs are rising three times faster in secondary care than in primary care, but many hospitals have not introduced cost control measures that were started in primary care years ago.
Just 40% of hospital trusts benchmark prescribing patterns across clinical teams and only 2% do so for individual prescribers, responses to a Freedom of Information request have revealed.
In total, 135 of the 166 hospital trusts in England responded to GP's request for information. Some trusts claimed implementing such benchmarking would be impossible or pointless.
Manchester GP Dr Anita Sharma, a member of Oldham medicines management committee, said hospital doctors' prescribing often showed 'little or no knowledge' of best practice.
She said the lack of cost controls in secondary care prescribing threatened efforts to achieve the efficiency targets required by the Quality, Innovation, Productivity and Prevention (QIPP) programme.
'Nothing will be achieved unless we work together to deliver the £20bn QIPP target,' she said.
GPC deputy chairman Dr Richard Vautrey said hospital prescribers needed to match the cost-effective prescribing efforts begun in primary care years ago.
'This is a process GPs have been through for the past two decades, but it is new for many hospital doctors,' he said.
Benchmarking prescribing patterns and educating doctors were important ways of improving prescribing, he said.
'Providing all clinicians with additional information about individual prescribing trends would be very useful.'
GP's investigation found one method hospital trusts are using to cut their drug spend is to push prescribing on to GPs.
Explicit guidelines are in place in more than 17% of trusts for GPs to be told to prescribe any non-urgent medicines, rather than medicines being supplied at the hospital's expense.
Dr Vautrey said that such measures needed to be avoided. 'We are all in this together,' he said. 'We need to get away from this division where a cost saved in one service is passed on to another service.'
GPs' efforts to control rising drug spending have meant annual cost rises have fallen to 1.5% a year in primary care, while hospital costs are expected to rise 7% annually, according to estimates from the Office of Health Economics.
Even when the additional cost of NICE-approved drugs in hospitals is taken into account, spending is rising three times faster than in primary care.
Dr Sharma said GP prescribing had been examined to 'microscopic' levels and that improved prescribing had led to better health outcomes.
'GPs have improved their organisational system to ensure safe and cost-effective prescribing,' she said.
'We have a system in place for prescribing, monitoring and review and we invest in improving the knowledge and skills of our staff.'
The same level of scrutiny now needed to be applied to hospital prescribers, she said.
'We need a greater consistency and standardisation and it is only fair if we have detailed analysis of secondary care prescribing.'
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