Prescription drugs provided to convicted criminals serving time in Irish jails have cost the taxpayer almost €14m in the past five years.
Figures released under the Freedom of Information Act reveal that an average of nearly €2.m is being spent on medications for prisoners every year.
The institution with the highest bill for prescription drugs was Wheatfield Place of Detention in Dublin, which spent over €2m on meds for its prisoners since 2009.
It was followed by Midlands Prison in Portlaoise, which provided prescription drugs worth €1.9m to its inmates during the same period. The prison has an operational capacity of 870, while Wheatfield can accommodate up to 550 prisoners.
Mountjoy Prison, which has a capacity of 554, spent €1.87, on prescription medications for its prisoners in the past five years.
The Dóchas Centre in Dublin, which is a medium-security prison for female offenders, has spent €635,817 on prescription drugs for its prisoners since 2009. It has an operational capacity of 105.
St Patrick's Institution, which is a place of detention for 17-year-old males, spent €222,155 on medications for its prisoners during the same time. It has a capacity of just 34.
A spokesman for the Irish Prison Service (IPS) said that efforts had been made to reduce the cost of prescription medications by using generic alternatives in recent years.
"The IPS has adopted a policy on the prescribing and use of generic medicines, which was developed and approved by the IPS Drug and Therapeutics Committee," he said.
"This policy states that generic medicines should be prescribed and consequently dispensed whenever and wherever possible as they deliver best value for money."
However, he noted that circumstances may arise in which a particular brand of medication is specified by the prescriber, and this is permitted within the stated policy.
"Unless otherwise indicated by the prescriber at the time of prescribing, the generic medicine is then dispensed and administered," the spokesman added.
Last year, the bill for prescription medications in the 14 prisons and detention facilities in the State was €2.28m; representing a decrease from €3.02m in 2012.
More than €2.83m was spent on prescription drugs for prisoners in the year prior to this, and €2.96m was spent in 2010. In 2009, prescription meds costing €2.83m were provided to prisoners in the State.