Patient Safety in Medication Nomenclature: Orthographic and Semantic Properties of International Nonproprietary Names

Abstract

BackgroundConfusion between look-alike and sound-alike (LASA) medication names (such as mercaptamine and mercaptopurine) accounts for up to one in four medication errors, threatening patient safety. Error reduction strategies include computerized physician order entry interventions, and ‘Tall Man’ lettering. The purpose of this study is to explore the medication name designation process, to elucidate properties that may prime the risk of confusion.Methods and FindingsWe analysed the formal and semantic properties of 7,987 International Non-proprietary Names (INNs), in relation to naming guidelines of the World Health Organization (WHO) INN programme, and have identified potential for errors. We explored: their linguistic properties, the underlying taxonomy of stems to indicate pharmacological interrelationships, and similarities between INNs. We used Microsoft Excel for analysis, including calculation of Levenshtein edit distance (LED). Compliance with WHO naming guidelines was inconsistent. Since the 1970s there has been a trend towards compliance in formal properties, such as word length, but longer names published in the 1950s and 1960s are still in use. The stems used to show pharmacological interrelationships are not spelled consistently and the guidelines do not impose an unequivocal order on them, making the meanings of INNs difficult to understand. Pairs of INNs sharing a stem (appropriately or not) often have high levels of similarity (<5 LED), and thus have greater potential for confusion.ConclusionsWe have revealed a tension between WHO guidelines stipulating use of stems to denote meaning, and the aim of reducing similarities in nomenclature. To mitigate this tension and reduce the risk of confusion, the stem system should be made clear and well ordered, so as to avoid compounding the risk of confusion at the clinical level. The interplay between the different WHO INN naming principles should be further examined, to better understand their implications for the problem of LASA errors.

Focus group discussions of registered nurses’ perceptions of challenges in the medication administration process

“…However, adding more verification practices seems futile, as deviations from safe practice still exist (Choo, Johnston, & Manias, ). Pharmaceutical companies should be cautious of LASA names for avoiding errors (Bryan, Aronson, Hacken, Williams, & Jordan, ), or similar packaging for different drugs. Important insights were nurses’ descriptions of the challenges related to the safe handling of drugs.…”

<p>Linguistic Factors in Arabic for Miscommunication of Medication Names</p>

“…Another potentially significant source of miscommunication arises from the visual processing of look-alike and sound-alike (LASA) drug names. 6 Algorithm-based methods such as the Levenshtein edit distance (LED) are used to identify potentially confusable names. The ability of such algorithms to identify confusable drug names in Arabic and English is a required area of further research.…”

16th ISoP Annual Meeting ‘‘Pharmacovigilance for Safer Tomorrow’’ Agra, India 16–19 October, 2016

“…So too could simulation testing of proposed regimens to determine the weak points where errors are likely to occur. However, many errors occur as a consequence of the confusion of names or appearances of medicines, and while there are protocols for avoiding look-alike and sound-alike errors, these are imperfect [12]. Regulators and applicants for market authorizations might be thought to have failed if they do not show due diligence in systematically assessing the risks of errors before marketing.…”