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Keywords:

  • look-alike;
  • medication safety;
  • pharmaceutical care;
  • sound-alike medicine names

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

Objective  To review current literature with the objective of developing strategies and recommendations to enhance patient safety and minimise clinical issues with look-alike, sound-alike medication names.

Methods  A comprehensive search of the PubMed database and an Australian online repository of Quality Use of Medicines projects was conducted to identify publications addressing look-alike, sound-alike medication problems. Author networks, grey literature and the reference lists of published articles were also used to identify additional material.

Key findings  Thirty-two publications describing the extent of the specific problem and recommending solutions were identified. The majority of these publications provided a qualitative assessment of the issues, with few quantitative estimates of the severity of the problem and very little intervention research. As a result, most recommendations for addressing the problem are the result of expert deliberations and not experimental research. This will affect the capacity of the recommendations to ameliorate and resolve problems caused by look-alike, sound-alike medication names. Themes identified from articles included the nature and causes of look-alike, sound-alike problems, potential solutions and recommendations.

Conclusions  There are many existing medications which can potentially cause clinical issues due to mix-ups because of similar sounding or looking medication names. This confusion can be lethal for some medication errors. A multifaceted, integrated approach involving all aspects of the medication use process, from initial naming of INN through to consumer education, is suggested to minimise this issue for medication safety.


Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

Medication safety is recognised as a high priority in many healthcare systems because many avoidable problems are caused by medications. Medication errors are considered among the most common medical errors[1,2] and have been noted to be of particular concern in paediatric medicine,[3] obstetrics and gynaecology,[4] anaesthesiology[5] and psychiatry.[2] For example, approximately half of the iatrogenic complications that occur in neonatal intensive-care settings are related to medication errors.[6]

Broadly speaking, medication errors can be characterised as errors in the prescribing (including dose calculations), supply (dispensing) or administration of medicines, which include the elements of drug ordering, transcribing, communication, product labelling, packaging and nomenclature, compounding, dispensing, distribution, administering, monitoring, education and use.[1,3] Interpreting the literature is complicated by variations in terminology. Twenty-six different definitions of medication error were identified in a review of 45 medication error studies.[7] The prevalence of errors in these studies ranged from 2–75%, but no associations were found between prevalence and definitions of error.[7]

In studies looking at all types of medication errors, prescribing errors accounted for the highest percentage,[7] although the administration stage has been identified as the point at which the most harm to patients occurs.[4] The most common dispensing errors found in community and hospital pharmacies are dispensing the wrong drug, strength, form or quantity, and labelling medication with incorrect directions.[8] All but the last of these errors can occur as a result of medications having similar looking or similar sounding names. Rates of dispensing errors vary widely depending on context (community or hospital pharmacy), whether prevented or unprevented errors are measured, how errors are defined and how rates are calculated.[8] Estimates range from less than 0.5% up to 24% of medications dispensed.[8] While the effects of medications errors vary widely, they have the potential to cause adverse drug events, some of which can have serious consequences for patients.[9]

Medicines being incorrectly chosen and administered inadvertently because of similar sounding or looking names has great potential to cause harm.[10] Tamoxifen/tenoxicam is an example of generic name potential confusion. Up to 25% of medication errors in the USA are reported to involve drug name confusion[11,12] and up to 33% are attributed to packaging and/or labelling confusion.[12] Both orthographic (i.e., spelling) and phonological (i.e., sound) similarity increase the probability of name recognition errors among both experts and novices.[11]

Australia has a National Medicines Policy, comprising four arms,[13] one of which is Quality Use of Medicines (QUM). A number of programmes and activities have been pioneered in Australia to improve how medicines are used safely and effectively. These have been collated and documented on the QUMmap (http://www.qummap.net.au). The Australian National Medicines Policy Committee commissioned the study reported here, which evaluates the issue of medicine names that may cause confusion by their similarities, either by sounding similar or by looking similar when written. This issue has international implications for clinical practice.

Aim of the review

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

This review was designed to collate and describe current research about look-alike, sound-alike medicine names, especially any research focussing on solving issues rather than just describing problems, to arrive at recommendations suitable for national implementation on possible ways to address this issue.

Methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

The published literature and the QUMmap (http://www.qummap.net.au) were searched. Material was included if it was published after 1995 and in English. Original research on interventions (rather than describing the issue) was sought, and opinion pieces were excluded.

The PubMed database was searched (November 2010) using the terms look-alike drugs, sound-alike drugs, slip errors medication, lapse errors medication and brand extension to discover any publications on the issue of look-alike, sound-alike medicines. The QUMmap was also searched in November 2010, using the terms look-alike, sound-alike, packaging, labelling, slip error, lapse error and brand extension.

The personal contacts and networks of the authors were used to discern any other information or resources, published or otherwise. The grey literature was searched, mainly by tapping into known resources and following the leads generated by the authors from their expertise and experience and any leads given by their network of contacts.

The reference lists of the literature identified in these ways were also scanned for further relevant articles. This was not intended to be a general review on medication safety issues, however, and hence the material was restricted to focus specifically upon the topic of look-alike, sound-alike medication names, and particularly on original research testing interventions. The information sourced was then assessed for relevance and summarised, drawing together themes and ideas. Due to the heterogeneity of the relevant material that was identified, no formal quality assessment or data extraction tools were used. Rather, the primary contributions of each piece of work to the problem of look-alike, sound-alike medicine use were identified and collated across all relevant material. Finally, a series of recommendations were formulated.

Results

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

Thirty-two publications that investigated the issues around look-alike, sound-alike medication naming were identified.[8,11,12,14–42] These articles, together with descriptive characteristics and conclusions are reported in Table 1. Twenty-four articles were journal articles but only 14 reported original research and none were of interventions to prevent medication errors from look-alike, sound-alike medications. There were insufficient data from well-designed studies to perform any sort of systematic review or meta-analysis. Most of the studies qualitatively identified issues of look-alike, sound-alike medication names. Quantitative estimates of the problem were lacking and very little robust research about interventions was found. There were several publications which were very general, and were mainly concerned with a range of medication safety issues rather than specifically with look-alike, sound-alike medication names. Findings were collated into topics including: published lists of confusable names, the contribution of look-alike, sound-alike names to medication errors, the types of look-alike, sound-alike medication name confusion that occur and the solutions that have been proposed.

Table 1. Articles included in review
ReferenceSource descriptionConclusions
  1. ACSQHC, Australian Council for Safety and Quality in Health Care; AHA, American Hospital Association; INN, international non-proprietary name; JCAHO, Joint Commission on Accreditation of Healthcare Organizations; LASA, look-alike, sound-alike; USP CAPS, United States Pharmacopeia Center for the Advancement of Patient Safety.

Lambert et al. (2001)[11]Type: journal articleDrug name similarity increases false recognition memory errors
Design: laboratory experiment
Berman (2004)[12]Type: journal articleSystems and recommendations are reported, which can reduce the occurrence of LASA medication errors
Design: overview
JCAHO (2005)[14]Type: journal articleDeveloped to assist healthcare organisations develop and maintain programmes to minimise risks from LASA drug names
Design: list and recommendations
Leape et al. (1995)[15]Type: journal articleSystems analysis is a better method for addressing medication errors in hospitals than is focussing on individuals
Design: systems analysis of data from prospective cohort study
Bates et al. (1995)[16]Type: journal articleAdverse drug events are common and most result from errors at the ordering stage
Design: prospective cohort study
Ferner et al. (2006)[17]Type: journal articleClassification of medication errors helps address the different probabilities and remedies for different classes of errors
Design: classification study
Schulmeister (2006)[18]Type: journal articleDescribes examples of LASA medication errors, describes some of their causes and suggests a range of risk reduction strategies
Design: overview
Cohen (2002)[19]Type: letter to the editorClarifies a number of perceived errors in an earlier article describing solutions to LASA medication problems
Design: error correction
Lee (2007)[20]Type: grey literatureThe problem of LASA medication packaging and labelling has grown and requires a policy response
Design: survey study
Phillips and Williams (2006)[21]Type: journal articleMedical errors involving LASA neuromuscular blocking medications continue to result in patient morbidity and mortality
Design: professional organisation statement
James et al. (2009)[8]Type: journal articleDevelopment of medication error reduction strategies is hampered by differences in definitions for dispensing errors, error rate and classification of error types
Design: review
Ashcroft et al. (2005)[22]Type: journal articleA wide range of medication errors occur in community pharmacies
Design: prospective study
Peterson et al. (1999)[23]Type: journal articleDispensing errors occur in greater numbers than those reported to regulatory authorities and appear to be caused by high prescription volumes, fatigue and overwork
Design: survey study
Hong et al. (2005)[24]Type: journal articleProduct line extensions help price rigidity in original brands
Design: retrospective follow-up study
AHA (2005)[25]Type: grey literatureProvides case studies and an action agenda for reducing errors from LASA drugs
Design: medication safety brief
Aronson (2004)[26]Type: journal articleRegulatory authorities and manufacturers should be vigilant when naming new drugs and formulations, in order to avoid drug name confusion
Design: editorial
Lambert et al. (2010)[27]Type: journal articleClinician and lay person ability to identify spoken drug names is affected by signal-to-noise ratio, subjective familiarity, prescribing frequency and the similarity of drug names
Design: laboratory experiment
Kenagy and Stein (2001)[28]Type: journal articleDrug names, labels and packaging are not chosen and designed in accordance with human factors principles and this contributes to medication errors that cause patient injuries and deaths
Design: overview
Santell and Cousins (2005)[29]Type: journal articleEfforts by regulatory authorities, drug manufacturers, pharmacists, other health care professionals and patients can reduce medication errors
Design: overview
Schwab et al. (2002)[30]Type: journal articleUsing trade names and omitting INNs can result in serious adverse drug events by overdose
Design: clinical observation
McCoy (2005)[31]Type: journal articleEvaluation of potential LASA medication errors should occur proactively
Design: case study
ACSQHC (2002)[32]Type: grey literatureReport seeks to increase general understanding of things that can go wrong with medicines, the size and nature of the problem in Australia, strategies that can make a difference and national directions being taken to improve medication safety
Design: report
USP CAPS (2004)[33]Type: grey literatureProvides a list of drug names that have caused confusion and reasons for that confusion
Design: report
US Pharmacopeia (2010)[34]Type: websiteProvides a free tool for accessing drug names that have been associated with medication errors, as well as evidence on how communicating drug orders can lead to medication errors
Design: database
Friedman (2005)[35]Type: journal articleHealthcare organisations should integrate JCAHO safety goals into their policies, procedures and clinician education, in order to avoid dangerous and costly medication errors
Design: overview
Kovacic and Chambers (2010)[36]Type: journal articleSpecialty areas of medical practice may require a proactive system for reviewing LASA drug name pairs
Design: orthographic analysis of drug names
Lambert (1997)[37]Type: journal articleAutomated measures of medication name similarities can be accurate, sensitive and specific
Design: observational retrospective
Kondrak and Dorr (2006)[38]Type: journal articleA new orthographic measure outperforms other commonly used measures of similarity for LASA drug names
Design: laboratory experiment
Filik et al. (2006)[39]Type: journal articleProvides some support for the use of tall-man lettering to reduce look-alike medication errors
Design: laboratory experiment
Filik et al. (2004)[40]Type: journal articleDrug names using tall-man lettering were less likely to be incorrectly identified
Design: laboratory experiment
Emmerton and Rizk (2010)[41]Type: conference paperProposes an interactive model for cautions about LASA medicines in community and hospital pharmacy
Design: review
Emery et al. (2010)[42]Type: conference paperContribution of increased use of generic medicines to labelling problems
Design: review

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

Published lists of confusable drug names

Various lists of look-alike, sound-alike names have been published, and many general medication safety publications describe the problem. For example, the US Joint Commission on Accreditation of Healthcare Organizations (JCAHO) published a ‘safety goal’ in 2005 highlighting the problem of look-alike, sound-alike medications.[14] They described confusing drug names as a common system failure and suggested that organisations (such as hospitals or pharmacies) conduct annual reviews of the look-alike, sound-alike drugs that they use. In Australia, such lists have been compiled (for example, by the Pharmacy Board of Victoria). However, the lists have not been widely adopted and there is no specific regulation in Australia to cease proliferation of look-alike, sound-alike names for new medicines.

A compiled list of look-alike, sound-alike medicines by the United States Pharmacopeia (USP) was provided in 2004.[33] Following this publication, USP developed a useful online search facility containing 1470 unique medications implicated in look-alike, sound-alike errors, contributing to more than 3170 confusing medicine name pairs.[34,43] The USP 2008 report provides information about the extent of the problem in the USA and the contribution of look-alike, sound-alike names to medication safety issues.[43] The US Institute for Safe Medication Practices (ISMP; http://www.ismp.org) publishes electronic subscription newsletters that report recently identified look-alike, sound-alike medication errors. This is a good source for timely information in the USA.

A list of 277 medication pairs was recently compiled as potentially causing confusion among medicines prescribed in Australia.[41] Of these medicine pairs, 267 were for unrelated medications, while 10 were for variations of the same drug.

Contribution to errors

Original, published and peer-reviewed research on the extent of the problem is limited. In two US tertiary care hospitals, 7% of adverse drug events (ADEs) over a 6-month period were the result of faulty medication identity checking, and most of those errors were identified as being due to confusion over medicines with similar names or similar packaging.[15] Most errors occurred at the ordering and administration stage. Other research suggests that name and labelling confusion is implicated in as many as half of all medication errors in the USA.[18] However, while it is likely that medication errors occur because of look-alike or sound-alike names, unclear labelling or poorly designed packaging, specific error rates and injuries associated with look-alike, sound-alike medicine names are unknown and difficult to estimate.[19,21]

A review of literature on dispensing errors identified look-alike, sound-alike medicine names as a subjectively reported factor contributing to dispensing errors.[8] A retrospective analysis of actual dispensing errors identified similar drug names as the second most common causes of such errors (the most common cause being workload issues).[8]

A small research project gave a subjective estimate of error rates, including near misses, from a group of pharmacists in South Australia as approximately 1% of all dispensings.[20] Pharmacists registered in Tasmania, Australia, identified similar or confusing drug names as important factors that contribute to dispensing errors in community pharmacies.[23] Pharmacists who had been professionally registered for a longer period of time found such confusion to be significantly less important than pharmacists registered for a shorter time period. Similarly, while improving labels and providing distinctive drug names were considered important factors in reducing dispensing errors a longer period of professional registration was again associated with less importance being placed on this.[23] These findings may be related to prescribing frequency being found important in drug name recall.[44] The associations between length of registration and both the importance of the problem, and the importance of improving labels, though significant, were weak.[23]

A study of community pharmacies in the UK identified a dispensing error rate of almost 4 per 10 000 items dispensed.[22] Similar drug names were found to be responsible for 16.8% of the errors recorded.

Consumers have also identified medication packaging and labelling, more generally, as major factors contributing to poor compliance and medication safety, particularly in the context of generic substitution.[42]

Types of problems

Aronsen has suggested that sources of confusion over medication names can arise from: different medications having similar names; formulations containing different medications sharing the same brand name; the same medicines marketed in different formulations having different brand names; and the use of abbreviated medication names.[26]

Brand extension, which is another problem causing confusion, refers to a new product that is a variation (e.g. new formulation or modified molecule) of an existing product.[24] Brand extensions are an effective way to support price rigidity in products that are going off-patent and can result in products with names similar to existing products. Brand extension leads to problems arising with drug names, particularly where products with different dosage forms are only indicated by the use of suffixes (e.g. XR, SR and XL in brand names for extended-release products, such as tramadol, tramadol XR, tramadol SR).[29] This has been identified as important for both prescription medicines and over-the-counter (OTC) medicines,[20] though it has been perceived to cause more confusion for prescription than for OTC medications.

The rate at which new drugs are introduced onto the market adds to the problem of look-alike, sound-alike medication names.[25] Kenagy and Stein suggest that the concept of ‘trade dress’ drives commercial considerations for naming, packaging and labelling.[28] Trade dress demands that a product projects an image of quality and, ultimately, that if something works (results in sales), that it should not be changed.[28] Unfortunately, adherence to this strategy for naming medications, including for brand-extension purposes, may not always serve the best interests of the consumer in terms of ensuring that they receive and take the intended medication.

Underlying this problem is the argument that existing pharmaceutical systems (prescribing, dispensing, administration) are flawed because they rely on human perfection.[28] That is, they often ignore important human factor concepts such as simplicity, standardisation, differentiation, lack of duplication and unambiguous communication in the process of drug naming, labelling and packaging. The result is drug names that look and sound alike. This can lead health professionals to unintended interchanges of medications with potentially serious clinical consequences for patients.[28] Lack of differentiation of medicine names may lead to slip/lapse errors as a class of medication error that results from the performance of an action that was not the intended action.[17] This type of error is facilitated when drugs have similar names, for example, a name like the intended medicine's name is written on a prescription; or when a product name that looks like the intended medicine name is selected in a dispensary.

Spoken medication orders can also be a source of slip/lapse errors and ambiguous communication errors for both clinicians and laypersons.[27] Accuracy in identifying spoken medicine names increases as the background noise levels decrease; when people are more familiar with a drug name; and when the national prescribing frequency of the drug is higher.[27] Other research has identified visual and auditory distractions, workflow and time pressures to be risks for the confusion of medicine names.[41]

Suggested solutions in the current literature

Research evidence for methods to reduce drug name confusion is rare. Nevertheless, a number of generally untested solutions to the problem of look-alike, sound-alike medication names have been promulgated.

Medication name remedies

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

In the context of spoken medication orders, the amount of background noise and familiarity effects are seen to be important targets for intervention to reduce errors.[27]

A strategy for managing look-alike, sound-alike drug name confusion used with oncology medicines[18,36] applied Levenshtein distance and Bigram similarity algorithms, same first and last letters and an online alert system to identify look-alike, sound-alike generic medicine names. Levenshtein distance is a measure of similarity in the ordering of a string of letters. It counts the total number of letter insertions, deletions or substitutions needed to change one name into the other. For example, applying the algorithm to Xanax and Zantac gives them a similarity score of three.[37] Bigram similarity looks at the number of adjacent letter pairs common to pairs of words. This approach has identified more potential medication name problems than were found in the published literature, possibly because most published lists are the result of voluntarily reported medication incidents. A proactive review of potential problems might contribute to averting errors with previously unidentified problem drugs.[36]

A model has been developed, also based on Levenshtein distance, which automates an orthographic approach to name comparisons, using similarities in the spelling of drug names to predict name confusion.[37] A distance value of five was found to provide a cut-off with high sensitivity and specificity. The method can provide agencies responsible for approving trademarks and drug names with a valid and reliable method for assessing the likelihood of look-alike, sound-alike medication name errors.[37] This method lacks features that manual evaluation of names by experts can provide – e.g. consideration of dosage, indication and physical appearance of the drug. However, as a computerised method, it allows the automated comparison of new drug names with the thousands of drug names already in existence.[37]

An alternative approach is to take advantage of the phonetic characteristics of individual sounds to estimate the similarity of names.[38] This does require phonetic transcription before analysis – but allows the identification of confusable words that orthographic methods do not pick up.[38] The highest accuracy in identifying confusable names is obtained by using a combination of orthographic and phonetic approaches.[38]

The likelihood of a medication name being confused is reduced, the more distinctive the name. This has led to the suggestion that the full names of drugs be used wherever possible (e.g. prednisolone sodium phosphate rather than prednisolone to reduce the risk of confusion with prednisone).[36] While it has been suggested that only generic names, or international non-proprietary names (INNs), be used in an effort to reduce look-alike, sound-alike errors involving proprietary (trade) names, it has also been suggested that only trade names be used to avoid confusion among similar sounding generic names.[12] The solution may be to use both generic as well as trade names (if one is available) for drugs with a known potential to cause confusion.[12] Including the indication on the prescription (and possibly the medication label) would also assist correct recognition of the appropriate medication name.[43]

Some research looks at the use of ‘tall-man’ letters; that is, uppercase letters, to differentiate sections of drug names that may sound or look alike.[39,45] An example from the Australian national tall-man lettering list aims to differentiate cefUROXime, cefOTAXime, and cefTAZIDime.[46] Research suggests that tall-man letters do not make names less confusable in memory but do make similar names easier to distinguish – if participants are aware that this is the purpose of the uppercase letters.[39] Other research suggests that tall-man letters can reduce the number of errors made in selecting a target medicine when faced with an array of medication packs.[40] Tall-man lettering has been reported to reduce medication name confusion in a number of different groups of people, of different ages and professions, in laboratory-based tasks.[45] However, an evaluation conducted for the UK National Health Service cautions a pragmatic approach to the widespread implementation of tall-man lettering and suggests that the prevalence of other more likely errors indicate the need for broad research rather than just this limited potential solution to one aspect of the problem.[47]

Dispensing and administration contexts

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

Some suggested solutions focus on the characteristics of the locations where people obtain and take medicines. Strategies for use at the health centre level include: adding special warning labels to identify medications with the potential to be confused; adding a verification step (by a second staff member) to the process of medication selection; publishing information bulletins warning of potential look-alike, sound-alike drug names; and proactively identifying potential look-alike products through the involvement of inventory control technicians.[31] No evaluation to determine whether this intensive programme reduces errors was reported.

Another strategy for managing look-alike, sound-alike drugs suggests using the JCAHO list of problematic drug names to: identify drugs that are used by a home-care or hospice organisation; review patient medication profiles; and conduct home medication management reviews.[35]

Other suggested risk reduction strategies have included: healthcare workers being kept aware of medications that look or sound alike; the installation of pop-up alerts and bar coding on computer systems; putting distinctive labels and warning stickers on storage bins; and storing confusable medications in non-adjacent locations.[18]

Bar coding of medicines is sometimes considered a promising approach to reducing the level of dispensing errors.[22] However, this is dependent on the correct medicine being ordered and so does not eliminate problems of confusion in actual prescription. It also relies on pharmaceutical companies following a consistent bar-coding convention.

Educating patients on the risks of look-alike, sound-alike medications has also been suggested as an important line of defence against this type of medication error.[17,35]

Comprehensive approaches

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

A systems approach to risk reduction suggests that solutions should be implemented at all levels; medication production, dispensing, preparation and administration stages. This includes manufacturers and regulatory authorities being vigilant when new medications are named.[7] Such an approach must be complemented with a consumer focus, including consumer education, access to pharmacist counselling, and ensuring that consumers know and feel empowered to ask questions.

Aronson has proposed a comprehensive list of actions that could be taken by regulatory agencies, pharmaceutical manufacturers, prescriber, pharmacists, and patients to reduce the risk of errors resulting from drug name confusion.[26] These form the foundation for Table 2. Similar actions have been proposed by groups including the World Health Organization.[10]

Table 2. Minimising potential patient harm from look-alike, sound-alike medication names (modified from actions proposed by Aronson[26])
GroupRecommended actions
  1. INN, international non-proprietary name; LASA, look-alike, sound-alike.

Prescribers– Inspect actual medicines a consumer is taking, especially when adverse events occur, and be vigilant for possible confusion due to similar names
– Report errors to the relevant government agency/ regulatory authority
– Use INNs, if possible, or the national generic name when prescribing
– Issue computer-printed prescriptions if possible; any handwritten prescriptions should be clearly written, using uppercase letters, and never abbreviated medicine names
– Check unfamiliar names of medicines that patients report they are taking
Consumers– Assume more responsibility for educating themselves about medicines they are taking, and asking questions of their health professionals
– Take actual medicines along to consultations with prescriber or pharmacist
– Tell each new prescriber about all medicines being taken
– Report any suspected medication adverse events to their pharmacist and prescriber
Pharmacists– Check that consumers recognise all the medicines they are taking
– Discuss all medications with consumers, including likelihood for any confusion due to similarly named medicines
– Clearly differentiate storage areas for medications with LASA names
– Include alerts on shelves for medications known to be at risk for mix-ups due to similar names
– Ask consumers for old containers when filling a new prescription
– Report errors to the relevant government agency/regulatory authority
– Liaise with prescribers, advising on potential for medication mix-ups due to LASA medication names
– Instigate systems for always double checking prescriptions
Pharmaceutical companies– Conduct market research on potential names with consumers, prescribers and pharmacists
– Use available software (using orthographic and phonetic approaches) to test for LASA names and choose alternatives least likely to be confused with medicines already available
– Cooperate in international process of choosing new names and be prepared to change brand names, worldwide, if necessary to avoid medication safety issues
– Use the same INN (generic) name when naming new formulations
– Emphasise INN above the brand name in all labelling, packaging and consumer or prescriber information
Regulatory authorities– Government agencies should use more regulatory muscle to enforce naming that does not risk patient safety
– Enforce use of INNs, rather than requiring different names in different jurisdictions
– Harmonise international use of proposed new proprietary names
– Use databases to compare existing names with proposed names (using software to test orthographic and phonetic LASA proposed names), so possible name confusion can be predicted and avoided by not becoming registered medications.

Lambert and colleagues argue that, since name similarity is easily and cheaply measured, steps should be taken to monitor and reduce similarity as a way to reduce the likelihood of drug name confusions to improve medication safety. This is sound advice, but difficult to implement on a national or international scale.[11]

A number of organisations have produced broad strategies aimed at preventing drug confusion (JCAHO, ISMP and the US National Coordination Council for Medication Error Reporting).[12,14] There is considerable overlap with previously described strategies. Additional recommendations include the unambiguous labelling of injectable and IV drug containers, and proposing that all prescriptions clearly specify medication strength, dosage, route of administration and frequency, even where there is only one accepted option. Finally, there is a strong endorsement for collaboration among all stakeholders to facilitate the design of packaging and labelling that minimises error.

In addition to the actions proposed in Table 2, further processes recommended to reduce problems for pharmacists to use with error-associated medications[29] include keeping patient medication profiles current, with sufficient information for pharmacists to evaluate the appropriateness of medication orders, reading product labels at least three times (e.g., when a product is selected, packaged and returned to the shelf) and counselling patients in order to provide an opportunity to ensure that an order has been dispensed correctly and that the patient understands the proper use of the medication.[29]

Finally, a medication safety issue brief for hospitals and health networks[25] suggests that actions to reduce errors from look-alike, sound-alike drugs should include organisations evaluating their formularies to identify medications that are prone to name confusion and that errors involving look-alike, sound-alike drugs are tracked, with the results used to educate staff. They also suggest providing drug name spelling with verbal orders, providing the intended use of the drug with the order, and conducting a ‘failure mode and effects analysis’ for all drugs being considered for inclusion on a formulary.

Barriers

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

Obstacles to changing names, labels or packages include: the nature of the problem; that standards for names, labels and packages do not incorporate human factors principles; and that most of the information on labelling and packaging problems is not systematic and comprehensive. There is also a barrier in the regulatory structure governing pharmaceuticals. Regulatory agencies do not yet ‘own’ the problem – they do not see it falling into their jurisdiction. A further issue is the mission of pharmaceutical companies.[28] Pharmaceutical companies do not consider design for safety to be their responsibility. They only feel bound to meet the regulatory demands for information on the package – placing responsibility for getting medicines mixed up squarely on the medication prescribers and users.[28]

Political will is required to overcome these barriers and to implement many of the solutions that have been proposed.

Study limitations

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

This review may not include all relevant research. Research that was not captured by the PubMed or QUMmap databases and that was also not identified in our follow-up procedures has not been reviewed. Furthermore, the variability of the included material, in terms of quality and type of information presented, precludes a simple summation of the content or the strength of the findings. Finally, excluding non-English language material may have resulted in relevant material, such as the approach taken by the French drug regulatory agency,[48] being omitted from this review.

Conclusions

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

A multifactorial approach is essential to overcome the threats to patient safety from look-alike, sound-alike medication names. Each aspect of the medication use process, from original choice of INN through to dispensing, administration and consumer education require integrated attention. Unfortunately there is still very little intervention research which can guide development and implementation of systems to improve this aspect of medication safety. Various naming guidance documents have been developed (for example in the EU and by USP) and there are now ways of checking for similarities in ‘sound’ and ‘look’ of names, some of which could be implemented in an automated fashion by companies and regulatory agencies. Differentiation through use of techniques such as tall-man lettering or through use of bar codes require more international validation before widespread adoption is possible. Organisational aspects, paying attention to human factors, in methods of storage design, workload and occupational design (such as minimising distractions) are possible, but again these require rigorous research before universal adoption of specific systems can be recommended. The benefits of empowering and encouraging consumers to ask questions about their medications should not be underestimated and is part of any comprehensive solution.

Many of the recommendations in the literature could be adopted in many countries, supported by a national programme of implementation. Given that some of the major obstacles to improvement are structural, political commitment from governments will be required, supported by appropriate safety structures in health facilities. Interestingly, there appears to be a dearth of research in this area internationally. The problems caused by look-alike and sound-alike drug names are well described; priority should be given to funding innovative solutions. A step has been taken in this direction with a recent evaluation of the new national tall-man lettering list in Australia.[49,50]

Declarations

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References

Conflict of interest

The Authors declare that they have no conflicts of interest to disclose.

Funding

The Australian Department of Health and Ageing, Woden, Australian Capital Territory, provided funding for and originally commissioned this review.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Aim of the review
  5. Methods
  6. Results
  7. Discussion
  8. Medication name remedies
  9. Dispensing and administration contexts
  10. Comprehensive approaches
  11. Barriers
  12. Study limitations
  13. Conclusions
  14. Declarations
  15. References
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