Some hospitals are not reporting all medication errors or "near misses", a new series of inspection reports have revealed.
Concerns over safety have emerged in the first inspections of how public hospitals are managing medication in a report by the Health Information and Quality Authority.
The first inspections were made on foot of research showing up to one-in-five readmissions to hospital within a year of discharge are medicines-related.
And 6pc of hospital discharge prescriptions were found to have a potentially severe medication prescribing error.
The inspections involved visits to seven hospitals in November and December, including Bantry General Hospital, Connolly Hospital, Naas General Hospital, Nenagh Hospital, Mater Misericordiae University Hospital, Sligo University Hospital and University Hospital Waterford.
Sean Egan, Hiqa's acting head of healthcare regulations, said that "error associated with medication use constitutes one of the major causes of patient harm in hospital.
"Medication safety should be a priority area for all acute hospitals as they seek to ensure a high-quality and safe service for patients."
It identified an immediate high risk at Bantry Hospital, which was using a protocol system to give drugs intravenously that had devised for Cork University Hospital, but which was not approved for suitability.
A number of examples of good practice in relation to medication safety were found in Naas, the Mater and Sligo hospitals.
The reports warned that some hospitals don't have the necessary resources to help promote safety in the use of medicines.
Internal drugs and therapeutics committee are essential to oversee how the hospital anticipates, monitors, identifies and responds to risk.