To characterise patient and medication-related patterns observed in drug-related pressure ulcers (DRPUs) and provide descriptive findings that may support future consensus-building.

Multicentre retrospective observational study.

20 hospitals across Japan participated in the study with hospital pharmacists specialised in PU care.

A total of 1113 hospitalised patients with existing PUs were included and classified into three groups (definite, probable and no-possibility of DRPUs) based on predefined criteria.

The primary outcome was the description of medication-related characteristics observed in each DRPU classification group, including polypharmacy, initiation of new medications and dose adjustments. Secondary outcomes included differences in ulcer characteristics and functional status across DRPU categories.

The definite group (n=128, 11.5%) showed a significantly higher prevalence of polypharmacy (83.6% vs 71.1% in the no-possibility group, p

Medication-related characteristics such as polypharmacy, initiation of new medications, dose modifications and use of antipsychotics were more frequently observed in the definite DRPU group. These descriptive findings may help characterise the clinical patterns of DRPUs and may inform future hypothesis generation.