Prescribing and deprescribing of atypical antipsychotics in older multimorbid patients.

Background In hospital practice, atypical antipsychotics are often used to manage delirium, sleep problems, agitation, or behavioural and psychological symptoms of dementia, while evidence remains uncertain regarding effectiveness and safety for those off-label indications. While guidelines to reduce inappropriate prescribing have been published, prescribing patterns in older multimorbid patients are not well understood. We thus aimed to investigate the patterns of prescribing and deprescribing of atypical antipsychotics over one year following an acute hospitalisation, as well as the appropriateness of prescriptions.Methods We conducted a longitudinal analysis using data from the OPERAM trial, a European multicentre study assessing hospital pharmacotherapy optimisation in multimorbid older patients aged 70 years or older in Switzerland, Ireland, Belgium and the Netherlands between 2016 and 2019. Data were collected at different time points: admission, discharge, two months post-discharge and one year post-discharge. Atypical antipsychotic prescriptions were classified as appropriate, off-label but accepted, or potentially inappropriate. Outcomes included the prevalence of atypical antipsychotic use at the different time points, deprescribing rates for appropriate and inappropriate prescriptions, and the incidence of new atypical antipsychotic prescriptions among patients not previously treated.Results The number of patients prescribed atypical antipsychotics increased from 88/2005 (4.4%) at admission to 116/1980 (5.9%) at discharge. At admission, 62.5% of these prescriptions were classified as potentially inappropriate. During hospitalisation, 20/53 (37.7%) patients with potentially inappropriate prescriptions either had the medication discontinued or were assigned a new diagnosis that justified the use under an off-label but accepted or otherwise appropriate indication. Additionally, 47 (2.5%) of the 1917 antipsychotic-naïve patients received a new prescription during index admission, with one third (36.2%) lacking a clear indication. Among those newly prescribed atypical antipsychotics without an appropriate indication during hospitalisation, only 58.3% had the medication discontinued within one year of follow-up.Conclusions This study highlights the substantial prevalence of potentially inappropriate atypical antipsychotic prescribing in older multimorbid patients, with no clearly documented indication in almost half of the prescriptions initiated during hospitalisation and slow deprescribing efforts leading to long-term medication risks. Improving prescribing practices through education, protocol-driven deprescribing, and post-discharge follow-up is essential to reduce inappropriate use, and ultimately enhance patient safety.Supplementary Information The online version contains supplementary material available at 10.1186/s12877-025-06579-0.