all are based at Leicestershire Partnership NHS Trust, Leicester, UK. AbstractPurpose -The purpose of this paper is to identify psychotropic medication being prescribed for people with intellectual disability "as and when required" (PRN); the indications, frequency of use, rate of poly-pharmacy and contribution of PRN medication towards this. The paper also aimed to identify individual and environmental factors associated with PRN medication prescribing. Design/methodology/approach -Data were collected from nursing and medical records for the 119 service users in the acute assessment and treatment unit and NHS residential care settings managed by specialist intellectual disability services covering Leicester, Leicestershire and Rutland over a month period. Data were analysed using descriptive statistics and logistic regression to calculate adjusted odds ratios for predictor variables. Findings -In total, 72 per cent of the service users were prescribed and 25 per cent were administered PRN medication over the study period. The most common indications for PRN prescribing were aggression and agitation. Lorazepam and chlorpromazine were the most frequently prescribed PRN medications. The rate of poly-pharmacy was 41 and 38 per cent of this was attributable to PRN medication. Male gender and history of challenging behaviour were found to be significant factors associated with PRN medication prescribing. Originality/value -PRN medications are commonly prescribed in people with intellectual disabilities and contribute to poly-pharmacy. Whilst PRN medication continues to remain an effective therapeutic option in situations where environmental and behavioural approaches are proving insufficient, their use should always be in conjunction with effective review mechanisms.