The Irish College of General Practitioners has said that the increase in chronic disease and an ageing population has meant a rise in the dispensing and cost of medicines.
It told the Joint Oireachtas Committee on Health that the annual spend on medicines is now about €2bn for the public health system.
Dr Mark Murphy, Chairperson of ICGP Communications, said that, while the GP takes the responsibility and assumes the risk for prescribing drugs, often GPs are not the original doctor who starts a medication, as that may come from a hospital doctor.
He said that, while prescribing ten or more drugs for people over 65 years has increased from 2% to 22%, studies show the odds of potentially inappropriate prescribing have reduced and GPs are doing a better job.
Dr Murphy also said that prescribing rates of anti-depressants reflect a lack of psychological therapies and a lack of social therapies.
The ICGP has called for drug savings to be reinvested in general practice.
ICGP Vice-President Dr John O'Brien said that pharmaceutical advertising in the national media indirectly promoting certain products has been an unwelcome development in recent years.
He said this should come under legislative control, as GPs are encountering demand for drugs and services which have a dubious cost-benefit.
He called on the committee to support a recommendation to ban non-governmental healthcare advertising, especially the indirect promotion of drugs in the media.
Head of the Department of General Practice at the Royal College of Surgeons of Ireland, Professor Tom Fahey, called for more electronic prescribing.
He said that prescribing in many hospitals remains a paper-based activity.
Communication in relation to medication for patients between hospitals, GPs and the pharmacy is also paper-based.
He said that this means that transcription, dosage and monitoring errors are more common and patients are at greater risk of adverse drug events.