ABSTRACT: Mental health nurses are increasingly encouraged to discuss and document the outcomes of their nursing practice in order to maximize the care that they offer clients. One frequent function performed by mental health nurses working in inpatient units is the administration of ‘as required’ (PRN) psychotropic medications. However, according to the literature, this important aspect of nursing practice has been poorly explored and studies that have been undertaken demonstrate that nursing documentation of PRN medication administration is often inadequate. This study presents the results of a descriptive study examining the administration of PRN psychotropic medication at a secure acute inpatient mental health unit attached to a regional hospital in Australia. Of major concern is the findings of inadequate or no documentation regarding PRN administration. In 41% of cases the results of the PRN administration was not documented in the nursing progress notes, in 38.6% of entries it was not possible to identify who initiated the request for medication and in 9.1% of cases no reason was given for the administration of PRN medication.