Trajectories of pro re nata (PRN) medication prescribing and administration in long-term care facilities

Little is known about changes in pro re nata (PRN) medication prescribing and administration in residential aged care facilities (RACFs) over time.

To determine the prevalence and factors associated with PRN medication administration in RACFs and examine changes over 12-months.

Secondary analyses utilizing data from the SIMPLER randomized controlled trial (n = 242 residents, 8 RACFs) was undertaken. PRN medication data were extracted from RACF medication charts. Factors associated with PRN medication administration in the preceding week were explored using multivariable logistic regression.

At baseline, 211 residents (87.2%) were prescribed ≥1 PRN medication, with 77 (36.5%) administered PRN medication in the preceding week. PRN administration was more likely in non-metropolitan areas, and less likely among residents with more severe dementia symptoms and greater dependence with activities of daily living. No significant differences in overall PRN prescribing or administration in 162 residents alive at 12-month follow-up were observed.

Despite being frequently prescribed, the contribution of PRNs to overall medication use in RACFs is small. PRN prescribing and administration was relatively static over 12-months despite likely changes in resident health status over this period, suggesting further exploration of PRN prescribing in relation to resident care needs may be warranted.