KEY MESSAGES

• IDO is involved in most high lethality acts of suicide presenting to Irish hospitals.
• Most IDO patients have a history of IDO.
• The majority of high lethality IDO presentations in Ireland involve prescription medications.
• Having a history of IDO and a current prescription for psychiatric medication are associated with engaging in IDO using prescription medication.
• On discharge, less than half of IDO cases using prescription medication had a prescription alteration made, with starting a new prescription being the most common alteration. A polypharmacy overdose (OD) and a current prescription for psychiatric medication are the two significant predictors of this alteration being made.
• Future research to examine the impact of such alterations, and of the follow-up care for IDO patients, is warranted.