The government's drugs watchdog is costing the NHS too much money, according to experts.
NICE recommends what treatments should be available on the NHS
The National Institute for Clinical Excellence was set up five years ago to advise ministers on what treatments should be available on the NHS.
But in an article in the British Medical Journal, University of York researchers say its decisions are proving too expensive for the NHS.
The institute and the Department of Health have rejected the claims.
The National Institute for Clinical Excellence has been controversial.
In June 2000, it sparked uproar when it ruled that the drug beta interferon should not be given to every patient with multiple sclerosis.
In August 2002, it came under fire again after it recommended that the drug Glivec should only be given to a handful of patients with leukaemia. It later changed its mind.
Another decision to limit the number of drugs available for treating patients with advanced colorectal cancer also sparked controversy.
The NHS is expected to implement all NICE recommendations. In some cases, this has proved to be expensive.
Writing in the BMJ, Professor Alan Maynard and colleagues said NICE should take more account of the cost of its recommendations.
They said the way it decided which treatments should be available on the NHS was "essentially arbitrary".
They suggested NICE should be given its own budget to fund these new treatments so that the NHS isn't saddled with the bill.
"Some of its recommendations have put pressure on the NHS," Professor Maynard told BBC News Online.
"Some of its decisions on cancer drugs and on dementia treatments have been questionable.
"In the case of some cancer drugs, they only add a few months onto a patient's live but they are extremely expensive. NICE is imposing huge burdens on the NHS."
Professor Maynard's team also argue that NICE should not only focus on which new treatments should be made available, but also advise on the withdrawal of existing ineffective or inefficient therapies.
Andrew Dillon, NICE chief executive, said Professor Maynard made some interesting points about NICE's role.
"Most of which are matters for ministers and the wider NHS to consider," he said.
"Although our recommendations make a big impact on patient care, the cost of the technologies we recommend is marginal (around 0.1%) on an NHS budget which exceeds £60bn.
"We think it important that there is a lively debate about our role and impact and Professor Maynard and colleagues' article is a welcome contribution."
A Department of Health spokesperson said: "NICE has played a key role in improving standards in the NHS and providing equity of access to treatments.
"It has driven forward work in these two key areas of government policy by publishing 13 clinical guidelines, and over 70 technology appraisals dealing with a wide range of conditions.
"A recent World Health Organization report into NICE's technology appraisal programme stated "NICE has developed a well-deserved reputation for innovation and methodological developments that represent an important model for technology appraisals internationally"."