Wastage of medicines in ambulatory care in Portugal

Abstract

Objective: To characterize the amount of medicines wasted in ambulatory care, Portugal, measured in quantity and value, due to: 1) inadequacy of medicines package sizes to the therapeutic regimen and 2) non-compliance to the treatment prescribed. Study Design: Prospective study. Local: National study carried out between September 2005 and September 2006. Population and Methods: First a questionnaire was administered in the pharmacy, in order to identify the patient and the therapeutic regimen prescribed. A second questionnaire was developed for telephone interview and applied after the predicted length of treatment (acute conditions) or at the end of the package size (therapeutics for chronic diseases). Inclusion criteria were: patients aged 18 or over, with at least one prescription from the Portuguese National Health Service and oral therapies for a first time use (excluding emergency medication). Wastage was measured in number of pharmaceutical units, percentage of daily defined doses (DDD) and costs. A simulation study was performed to determine which package sizes would minimize the wastage due to the inadequacy of package sizes. Results: A sample of 1.601 patients which purchase 2.098 medicines. The mean age was 50 years old and 68.6% of patients were females. The global wastage was identified in 21.7% of the quantity prescribed in DDD. About one half (9,7%) was due to the inadequacy of the pack sizes, and the remaining (10,2%) due to non-compliance to the treatment prescribed. The average wastage cost per medicine dispensed was 4.44 . Conclusions: Medicines wastage found in this national study could be a good support for upcoming studies that can lead to optimize information for decision makers in this area. The simulation study showed that this could be reduced if other package sizes where available. Wastage due to non-compliance should be targeted in clinical practice in order to optimize patients health related outcomes.