Pharmacists should be able to offer patients cheaper drugs as an alternative to more expensive brands prescribed by GPs, experts have claimed.

The Economic and Social Research Institute (ERSI) has recommended that, provided two drugs have the same chemical properties and the same effect, patients should have the option to choose whether they buy a brand name.

Paul Gorecki, research professor at the think-tank, said this would save the Department of Health and the taxpayer money, and encourage competition in the pharmaceutical market.

"If you think of a drug it has several names - a brand name by the manufacturer, which is protected by a trademark, and its general chemical name," he said. "For example, Valium is the brand name and Diazepam its chemical name."

He said when a GP writes a prescription for a patient, the pharmacist must dispense exactly what is written. A previous study by the Health Service Executive found that if this practice were reversed, it could save around 77 million euro a year.

GPs tend to prescribe brand names to patients because they are likely to have heard of them over non-branded alternatives, the expert added. He said the power of pharmaceutical advertising inspires confidence in patients.

The Government pledged to reduce costs in the medical and pharmaceutical sectors in the memorandum of understanding it signed with the IMF last year and the ESRI said "significant progress" had been made.

Mr Gorecki said, should the Government pass legislation giving pharmacists the power to offer patients a choice of which drugs they receive, efforts must be made to ensure the different types of medication on offer are exactly the same.

According to the ESRI, pharmaceuticals account for 17.5% of public health expenditure, up from 14% in 2000. Expenditure per head in Ireland was among the highest of all Organisation for Economic Co-operation and Development countries.

"If this policy were passed as legislation, it would lower the cost to the taxpayer and involve them receiving better value," Mr Gorecki added.