A £90m cash injection by the government has failed to wipe out an overspending crisis caused by the soaring cost of unbranded drugs.

Primary care groups say many have yet to see their share of the money, which health secretary Alan Milburn announced at the end of December.

Dr Alistair Lipp, public health consultant at Norfolk health authority, who has been studying the crisis, said the one-off injection was 'very welcome' but could not clear the whole overspend.

'Ministers have been overwhelmed by the rise in price of generic drugs. It has had a significant effect on expenditure and a demoralising effect on GPs who have set out to improve their prescribing, ' he said.

Spending on prescribed drugs in Norfolk usually grows by 3 per cent a year, but this year the HA is facing a 6 per cent increase, he added.

The cost of many generic drugs - which GPs have been encouraged to prescribe as a cheaper alternative to brandname medicines - has doubled since last August, according to Dr Lipp's research.

The net ingredient cost of 'category D' drugs has jumped from£1.50 to£3 per item in the past six months.

Shortages mean that many generic drugs have been placed in category D, allowing pharmacists to dispense more expensive brand-name medicines when they cannot obtain supplies of the generic drug named on the prescription.

Norwich City PCG chief executive Dr Chris Price said the money 'won't be anything like enough' to cover the debts of Norfolk's eight PCGs, predicted to be£3.5m by the end of this financial year.

Primary care representatives who have held talks with the government over the issue say Department of Health officials have indicated that HAs should 'bail PCGs out'.

But Dr Price said Norfolk and many other HAs would be unable to cover PCG debts 'unless we see a sudden downturn in the cost of generics'.

He added: 'At the moment the rise is not even slowing.'

Other PCGs confirmed that debts were outstripping the extra funding. David Dawes, chief executive of East Manchester PCG, said his latest figures showed a predicted shortfall of£600,000 for his group alone.

'We are still waiting until we know what share of the£90m we have, ' he said.

He is budgeting for a jump of up to 9 per cent in drug spending at the end of this financial year in March.

'We will have to decide what we can't fund. This overspend has brought primary care development to a full stop.'

Dr Ron Singer, a board member of Edmonton PCG in north London, has also not heard how much government funding is due.

Edmonton was expecting to spend an extra£200,000 on prescribing, up to 12 per cent on what it had budgeted for, he said.

'I am fed up tinkering with tiny amounts of money just to pay the bills. It is pathetic. We should be worrying about providing healthcare not trying to find a penny for the meter.'

An investigation into generic drug prices ordered by junior health minister Lord Hunt is due to report this summer.