The head of the NHS drug approval body today calls on healthcare trusts to end Britain's "postcode lottery" for prescribing drugs. Andrew Dillon, chief executive of the National Institute for Health and Clinical Excellence (Nice), said that primary care trusts (PCTs) should be consistent in deciding whether to make funds available for drugs.

His comments follow growing public anger over the number of medicines and treatments being blocked by Nice.

"It shouldn't make any difference where you live," Mr Dillon told an edition of the BBC's Panorama, to be screened tonight.

"There ought to be a common basis for decisions about exceptional circumstances. Anybody who uses the NHS for their care is entitled to expect that.

"What patients need to do is to find out from those who are making the decision what the basis of that decision is, and if they don't think it's reasonable, if they don't think it compares appropriately with decisions that are taken elsewhere, ask, 'why not?'"

NHS trusts have a legal obligation to provide treatments approved by Nice. But in the absence of such approval, a patient must appeal to a committee at the local trust, which may fund it as an exceptional case.

Those who are refused must settle for a less effective treatment or pay privately for the drugs – at the risk of having all other NHS care withdrawn.

His comments came as the chairman of Nice, Professor Sir Michael Rawlins, warned that pharmaceutical companies were driving up the price of vital new medicines in order to boost profits and protect executive bonuses. Nice has been heavily criticised for turning down approval for drugs on the grounds that they are not cost-effective.

But Professor Rawlins said: "We are told we are being mean all the time, but what nobody mentions is why the drugs are so expensive," he said.

He said that one of the reasons was the need for companies to keep their share prices high. "Pharmaceutical companies have enjoyed double-digit growth year on year and they are out to sustain that, not least because their senior management's earnings are related to the share price.

"It's not in their interests to take less profit, personally as well as from the point of view of the business. All these perverse incentives drive the price up."

Professor Rawlins said that companies were also facing a drop in profits as some of their biggest earners went "off patent", allowing rivals to produce cheaper versions. "And so part of the cost is cushioning against that," he said.

The companies also had to cover the cost of marketing new drugs, which could far outstrip the cost of actually developing them.

"Marketing costs generally are about twice the spend on research and development," he said.

He said that many firms had taken a view that they would charge as much as they could get away with.

"Traditionally the pharmaceutical industry will admit that they actually charge what they think the market will bear. The wiser ones are recognising that that model is no longer available," he said.