217 consecutive admissions to an acute geriatric care facility in a teaching hospital were prospectively evaluated to assess the prevalence of drug related problems (DRPs) contributing to admission. DRPs were considered to include adverse drug reactions (ADRs), toxic overdose and poor compliance leading to therapeutic failure. The prevalence of DRPs on admission was 22.1% of total patients or 24.0% of those on prescribed medication at the time of admission. DRPs comprised 41 cases (85.4%) of ADRs, 1 case (2.1%) of exacerbated disease due to withdrawal of medication by the prescriber, and 6 cases (12.5%) of patient non‐compliance. DRPs were significantly associated with both the total number of immediate pre‐admission medications and the presence of a previous history of ADR. No other significant associations were found. The results suggest that prescriber behaviour, as opposed to patient behaviour, is a major contributor to DRPs and accordingly indicate the need for education of doctors about the risks of polypharm