Abstract Background Inappropriate prescribing (IP) is highly prevalent in older adults and is associated with increased risk of adverse drug reactions, increased morbidity, mortality and healthcare utilisation. Risk factors associated with IP include older age, polypharmacy and having multiple healthcare providers. The aim of our study was to identify the prevalence of polypharmacy and potential IP in the day hospital setting. Methods Patients attending our day hospital over two months were included. Consensus was reached between two Geriatric medicine SpRs and the day hospital pharmacist regarding various categories of potentially IP, and a proforma was agreed. We gathered demographic data, number of medications and subjective medication burden. We recorded data in Excel, and we quantified potentially inappropriate medicines and categorised all identified IP. Results 179 participants were included, mean age 83 (range 68-98). 80% of patients were taking ≥5 medications, overall, 40% perceived they were taking too many. 79% of participants had at least one example of IP, 25% had ≥3. The commonest example of IP involved PPIs, involving 26% participants, followed by antihypertensives involving 21% of participants. Overall, 48% of potentially inappropriate medications were identified due to ‘inappropriate indication’, and 37% related to side-effects. People aged 65-69 and 90-94 were the most likely to report they were taking too many medicines, 75% and 46% respectively. This correlated with the same age brackets having the highest number of average IP, 2.75 and 2.2 respectively. Conclusion Despite the well-known associated risk of harm, our study confirms ongoing high prevalence of polypharmacy and IP amongst older adults. Prescriber vigilance is key in reducing harm. Regular presence of a pharmacist, liaising strongly with medical staff, is invaluable in the day hospital setting.