Using discrete event simulation to design a more efficient hospital pharmacy for outpatients.

We present the findings of a discrete event simulation study of the hospital pharmacy outpatient dispensing systems at two London hospitals. Having created a model and established its face validity, we tested scenarios to estimate the likely impact of changes in prescription workload, staffing levels and skill-mix, and utilisation of the dispensaries' automatic dispensing robots. The scenarios were compared in terms of mean prescription turnaround times and percentage of prescriptions completed within 45 min. The findings are being used to support business cases for changes in staffing levels and skill-mix in response to changes in workload.