Patient Perspectives on Handling Single-Dose versus Multi-Dose Eye Drops: A Cross-Over Study.

Background: There is a lack of data evaluating the relative usability of single-dose and multi-dose containers for delivery of eye drops. This study aimed to evaluate the usability, convenience and patient preferences of eye drops in single- versus multi-dose containers. Methods: A prospective, open-label, multicentre, cross-over study was conducted in Portugal between April and June 2017. Participants aged 50 years or older and had indications for eye lubricant use were included. The participants were allocated to use either multi-dose or single-dose containers followed by switching during the study period. The usability, convenience and patient preferences of each eye drop containers were collected using a novel questionnaire developed by the authors of this study. Descriptive statistical analyses were performed for all outcomes. Results: A total of 114 participants completed the study. Overall, participants found the use of multi-dose containers easier than single-dose containers based on ease of container opening and ease of eye drop application. Multi-dose containers were less likely to have drops remaining in the container at disposal and had improved legibility of labels versus single-dose containers. Conclusion: The findings suggest that multi-dose eye drop containers were associated with better handling and use compared with single-dose containers.