Look-alike/sound-alike medication errors: An in-depth examination through a hospital case study

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Teeraporn Sadira Supapaan https://orcid.org/0000-0002-6887-8181
Ananya Songmuang https://orcid.org/0009-0004-8709-339X
Jintana Napaporn https://orcid.org/0009-0006-5580-8041
Parichat Sangsukwow
Pornchanok Boonrod
Phonrawin Intarapongsakul
Aporn Jaturapattarawong
Chonladda Pitchayajittipong


look-alike sound-alike (LASA), medication error, hospital, Thailand


Background: Look-alike/sound-alike (LASA) drugs substantially contribute to global healthcare challenges and patient harm, necessitating a comprehensive understanding of LASA medication errors. Objective: The current study explored the prevalence and characteristics of medication errors related to LASA in a 200-bed general hospital. Methods: A mixed-methods approach was employed. The quantitative component analyzed the LASA drug error data using the hospital database. For the qualitative component, in-depth interviews with pharmacists and pharmacy staff were undertaken to gain insights into stakeholder perceptions and management of LASA-related issues. Results: Quantitative analysis highlighted three types of LASA medication errors: confusion due to similar drug names, appearance, and packaging. Drug name confusion accounted for most errors (64.62%), demonstrating the considerable risk associated with similar medication names. Packaging confusion accounted for 24.61% of errors, indicating the importance of a unique packaging design. Overall, 10.77% of errors were attributed to similar appearance, indicating that the visual resemblance of medications played a considerable role in LASA errors. Forty-six LASA drug pairs were identified, the most frequent being simvastatin 10 mg and simvastatin 20 mg. The errors were divided into two categories: Category A, with two pairs related to name and packaging similarities, and Category B, with 44 pairs involving all types of similarities. The differentiation between these categories underscores the complex nature of LASA errors. Semi-structured interviews revealed that anticipatory errors often occurred during busy periods, which could result in crucial details, such as drug strengths, being overlooked. Proposed solutions for reducing LASA errors included implementing Tall Man lettering, developing movable LASA signage, and improving workforce allocation. Root-cause analysis identified several factors, including drug similarities and staffing issues, as notable contributors to LASA errors, highlighting the need for a multipronged approach. Conclusion: LASA medication errors, particularly those attributed to drug name similarities, pose a considerable risk and persist despite existing safeguards. Implementing tailored strategies, such as Tall Man letters, movable LASA signage, and careful management of high-risk medication pairs, could aid in addressing these issues.

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