A narrative review on do’s and don’ts in prescription label writing – lessons for pharmacists

Introduction

Pharmacist is the link between the prescriber and the patient. Therapeutic intentions of the prescriber is usually written in the form of a medical prescription. The pharmacist will then dispense medicines according to the prescription, together with essential medicines information without which patients may misuse medicines leading to adverse drug events¹ or alternatively, therapeutic failure.² The waste of resources due to misuse of medication is costly to both the patient and the country, and costs millions in expenditure.³ Further, it has also been reported that patient knowledge concerning patient-centered contents of medication labels is significantly associated with quality of life among older adults.⁴ The pharmacist, therefore, is the community pivotal point for providing correct, comprehensible and readable medicines information to patients in order to facilitate proper use of medicines.⁵

Medicines information may be written or verbal. Written forms may be presented in the form of dispensing labels, auxiliary labels, manufacture labels and even patient information leaflets. However, it is clear that there are weak links in the communication chain between health care professionals and patients. First, some or all of the important information may not be communicated to patients at all.^6,7 Research has shown that only 35% of patients receive information about their medicines from their primary care provider, 46% from pharmacist, while 32% received from neither.⁸ Second, some information even if delivered by the health care professional may be incomprehensible to the patient depending on the educational standards and their cognitive ability, which in turn may be due to health-related or other factors. Consequently, patients may find it difficult to read, understand or even recall the information provided.⁹ The level of understanding of prescription label instructions vary, and ranged from 53% to 89% in some studies conducted in the USA.¹⁰ It is also known that poor readability significantly affects comprehensibility and medication recall.¹¹ Hence, practicing pharmacist may find it useful to know the factors that hinder effective communication of medicines information in order to improve the process.

The depth of information to be provided greatly depends on the type of medicine. As far as the patient is concerned, he/she needs to have minimum data such as the name, strength, frequency, duration, route of administration and important cautionary information on their medicines. Hence, dispensing labels which contain dosing instruction on correctly administering medicines and auxiliary labels to warn patient on important cautionary information about the medicine are key essentials.

Shrank et al¹² and Bailey et al¹³ conducted two systematic reviews, both aimed at summarizing best practices in written prescription medication information and instructions to patients using related articles published from 1990 to 2015. These reviews also included physician–patient communication about medications and were not specifically focused on communication between patient and pharmacist. The role of the pharmacists in providing medicines information is different to that of the prescriber in many ways. The pharmacist is the last health care professional to care for patients at the outpatient setting, and is expected to transcribe the medical terminology on the prescription to simple instructions for the patient to follow. In that, the pharmacist is expected to ascertain the patient’s level of comprehension through a brief interview and adjust the level of communication accordingly. The pharmacist may even be the only health care professional encountered by a patient when purchasing over-the-counter medication at the pharmacy. Hence, this review aims to focus exclusively on patient and label-specific factors that lead to patient misunderstanding of the prescription instructions and auxiliary labels, given by pharmacists, and identify successful interventions that helped to improve this issue. As this review aims to collate studies that support a non-controversial aspect in patient communication, a narrative review approach was deemed appropriate.

Methods

Information was searched by a research pharmacist (reviewer 1) and a senior academic pharmacist (reviewer 2) using electronic resources, PubMed, Google Scholar and SAGE in April 2017. Search terms used were “drug dosing instructions”, “prescription medication label”, “prescription labels” and “dispensing labels”. All types of research designs except opinions and editorials published from year 2000 to April 2017 were included. The first reviewer read the titles and the abstracts and selected articles for review using the following inclusion and exclusion criteria.

Inclusion criteria

• Articles written in English language.
• Articles published in year 2000 and after.
• Articles including studies that focused on communication with patients.
• Articles including studies related to dispensing/prescription labels or auxiliary labels for prescription only medicines.

Exclusion criteria

• Articles that focused on manufacture labels, patient information leaflets and product information leaflets.
• Articles that focused on non-prescription medicines; off-label indications; devices; biologics; chemotherapy; herbal, dietary and non-medicinal preparations and investigational medicines.
• Opinions and editorials.

Cited references of selected articles were also included where relevant. A second reviewer went through the same process to endorse the selection of articles. Discrepancies were resolved through discussion among the two reviewers until 100% agreement was reached. A critical appraisal of articles was not performed using a formal checklist, but reviewers used self-judgment to appraise the studies before selection.

Results

A total of 33 articles that matched the objectives of this review were retrieved and evaluated by all three authors (Table 1). The findings of factors that lead to poor communication between pharmacist and patient when providing medicines information on dispensing/prescription labels and auxiliary labels, and interventions that were used to alleviate these problems were categorized as “patient-related factors” and “medication label-related factors” and are summarized in the following section.

Table 1 Summary of studies reviewed

Patient-related factors

Patient literacy levels and language barriers

Studies on readability and comprehensibility of dispensing labels or auxiliary labels reflect various factors that lead to poor communication. Among them, low level of literacy among patients was a major contributing factor.^10,14–17 Davis et al¹⁴ reported that low literacy rates were independently correlated to misunderstanding of written dosing instructions. In their study, patients with low level of literacy were found to be 3.4 times less likely to correctly interpret prescriptions and medication warning labels.¹⁵ Bailey et al¹⁸ found that low literacy rates was a risk factor for misunderstanding dosing instructions which also differed among different races. A large study by Masland et al¹⁹ among 48,968 participants found that among all participants who had limited English proficiency, 25% found it difficult to understand prescription bottle labels compared to only 5% among those who were proficient in English. The study concluded that prescription instructions must be compatible with patients’ educational level and culture. Bailey et al²⁰ reported that using concordant prescription instructions can help to improve safe medication use among limited English proficient patients.

Age of patients

Tai et al²¹ reported that age is a common significant predictor of prescription label comprehension and simple educational interventions such as one-on-one education provided on critical elements of the label could significantly improve the level of comprehension of prescription labels.

Medication label-related factors

Number of medicines dispensed

Taking a larger number of prescribed medicines was associated with poor patient comprehension of prescription labels.¹⁴ Patients were more likely to misinterpret dosing instructions when the number of medicines in a prescription was high. The authors of this study related this finding to high complexity of dosing instructions leading to confusion.¹⁴ In addition, the consistency of dosing instructions provided also varied among pharmacists in the community.²² This implies that pharmacists generally do not adhere to standard guidelines for providing vital medicines information that needs to be communicated to patients.

Format and organization of instructions

The format of the prescription label, the organization, spacing, headers, font style and font size, are critical features for promoting readable and understandable dosing instructions.²⁰ Most prescription labels emphasized less important information and gave little prominence to vital dosing instructions. Pharmacy name and logo were prominent in most labels while medication instructions, medication name, warning instructions and stickers were in smaller fonts.^12,22,23 Although larger fonts were readable by most patients,^11,24 nearly half of the labels did not comply with the minimum standard guidelines of 12-point font size specified for vital medicines information.^12,25,26 It was interesting to note that medication labels with better content and cosmetic appearance were preferred by the majority of physicians (75.3%), pharmacists (76.4%) and patients.²⁶ Leat et al²⁴ emphasize on the improvements to the label by including larger print size, a consistent layout with left justification and using upper case with highlighting for emphasizing of numbers in the instructions. A focus group including 17 participants revealed the importance of including pharmacy phone numbers, white space and highlighting in dispensing labels.²⁷ On the contrary, Chan and Hassali²⁸ used medicine labels with larger fonts but found no significant change in comprehension and medication adherence.

Complexity of dosing instructions

Common sense dictates that and many have confirmed the importance of providing fairly simple and lucid dosing instructions when dispensing any medication.^12,13,29 Labels with multistep instructions,^15,17 ambiguous instructions¹⁶ and imprecise instructions were often regarded by patients as complex.^10,13 Multistep instructions were found to be difficult for all patients irrespective of the literacy levels.¹⁵ Even a simple multistep instruction such as “take with food at night” was more difficult to comprehend than a single-step instruction such as “take with food”.¹⁵

Precision of dosing instructions

Labels with precise wording were more comprehensible to patients. Interestingly, a dosing instruction given as “take one tablet twice a day” or “take one tablet 12 hourly” was more difficult to understand than “take one tablet each in the morning and night”.¹⁰ Interventions to support best practices in writing dosing frequencies are numerous. Wolf et al³⁰ developed and tested the effectiveness of patient-centered labels (PCLs), one written with explicit timing (morning, noon, evening and bed time) and another with explicit timing accompanied with graphics, against a standard label with dosing instructions written as once, twice and thrice per day (“times per day” approach). They reported that PCLs were more likely to be correctly interpreted than standard labels, especially by patients with low level of literacy.³⁰ Further, a subsequent, improved version of the PCL developed using evidence-based information by the same group of researchers also showed improvement in proper use of medicines.³¹ A similar study by Sahm et al³² also supported this finding. Another study by Davis et al¹⁰ where mock medicine labels were prepared with dosing frequencies specified in “times per day” approach (e.g., three times a day), hourly intervals (e.g., every 8 hourly), time periods (morning, noon and night) and specific times (e.g., 8 am, 12.00 noon and 8 pm) reported that dosing instructions stated in time periods and specific times were more likely to be correctly interpreted. Bailey et al²⁰ used standard instructions (e.g., TAKE TWO TABLETS TWICE DAILY) written in uppercase lettering and “times per day” approach, against concordant instructions (e.g., Take 2 pills in the morning and 2 pills at bedtime) using explicit and simpler terms, lower and upper case lettering and numeric characters. Patients having concordant instructions understood dosing instructions and accurately dosed their medication better than those who received standard instructions. Hence, pharmacists must try to specify “time periods” instead of “times per day” and “specific times” instead of “hourly intervals”, when writing medicine frequencies.

Use of icons, graphics and pictograms

The use of icons, pictograms and graphics in labels received mixed responses from patients. According to some reviewers, icons, pictographs and prescription warning labels were frequently misunderstood by patients.^12,33 Prescription warning labels were also given less attention by older patients³⁴ and they preferred warnings to be given in the main label and not in auxiliary labels.³⁵ There was variability in comprehending pictographs among patients as well as medical staff.³⁶ Davis et al,¹⁵ for instance, summarized common misinterpretations of pictographic drug warning labels. Chan and Hassali²⁸ found no significant change in comprehension of information nor improved medication adherence due to pictograms. However, Wolf et al³⁷ noted that icons or pictograms were useful, particularly for the low literates. The latter author also studied the usefulness of auxiliary labels where patient-centered auxiliary labels were prepared using clear, concise and explicit language. Patient-centered icons were included after considering patient feedback and following guidelines established by the International Organization for Standardization for the Development and Testing of Universal Icons.³⁷ Auxiliary labels with simplified text only, and simplified text with icons, were more likely to be correctly interpreted compared with standard auxiliary labels. Between the two, labels with simplified text supported by icons were better interpreted than simplified text alone.³⁷ A study by Emich et al³⁸ also supports this claim where acceptability of three types of warning labels were assessed among patients taking driving-impairing medicines. Among three types of labels, a conventional yellow/black label, label with a rating model (risk level of driving) and a label with rating model accompanied with side-text, patients preferred the latter. Auxiliary labels attached to more prominent places of the label were better received by patients.³⁷ Addition of a color code to represent the indication of the medicine was also found to significantly improve the ability to accurately match their medication to indications.³⁹ Shiyanbola et al⁴⁰ redesigned patient warning labels using feedback from pharmacists and patients, on words (content), picture and color (cosmetic appearance) and placement of warning instructions on the pill bottle (convenience). They found that preferences of patients on design changes to improve understandability of warning labels were not always similar to that of the pharmacist, indicating differences in patient’s perspective to health care professionals. Both groups agreed on the preferred location of the warning label on the medicine pack and the use of color for drawing patients’ attention. Another study by Shiyanbola et al⁴¹ describes the outcome of a qualitative study using different variations of the five most commonly used warning labels: “Take with Food”, “Do not Drink Alcohol”, “Take with a Full glass of Water”, “Do not Chew or Break” and “Protect from Sunlight”. While appreciating the efforts, patients demanded further improvements to the content and design of the warning label to enhance clarity and understandability,⁴¹ depicting the importance patients place on clarity of information provided through warning labels. The same research group investigated perception on warning labels among an undeserved population and found that most rated the warning instructions to be extremely important and thought the graphics made the label information easy to understand. However, those who were currently not on medication and those with limited health literacy overlooked warning labels.⁴² Moreover, these participants preferred to be counseled by pharmacists on the important facts about the warning labels.⁴²

Discussion

The foregoing is a narrative review of the currently available data and factors that affect the readability and comprehensibility of medicine labels written by pharmacists. We noted that 1) patient literacy levels, 2) age, 3) number of medicines dispensed, 4) format and organization of the medicines label, 5) complexity of dosing instructions, 6) precision of writing dosing instructions and 7) the use of icons, graphics and pictograms were aspects that were frequently assessed by research groups on medicine label writing. In general, our review findings support the notion that instructions written in a simple and straight forward manner were better comprehended by patients.

Effective communication may not always ensure medication adherence among patients. From the available and reviewed data, it is difficult to conclude whether readability and comprehensibility of dosing instructions are directly related to medicines adherence. Shrank et al,²⁹ for instance, recently evaluated the effect of a number of improved features of labels on medication adherence. For this purpose, he incorporated flattened bottles with larger space to present the information and used larger font with more white space to improve prominence of the content as well as logical representation of information preferred by patients through evidence-based information. The new label also included a pocket to store medicines information. Interestingly though, the results from this study did not reveal a significant change in medication adherence of the participants due to the improved format of the presentation.²⁹ Chan and Hassali also concluded that improved medicine labels do not affect medicine adherence.²⁸ Moisan et al⁴³ conducted face-to-face interviews among 325 participants and found 38.8% were not able to read all the prescription labels and 67.1% did not fully understand all the information. However, the two variables were not directly related to adherence after adjusting for several factors such as gender, age, living alone or not, having help of caregiver when taking medication, assistance of a pill organizer, financial capability to procure his medicine during the previous month, attitude and efficacy of medication used, self-perception of status of health, satisfaction of information provided by health care professionals and complexity of the treatment.

However, Shanika et al⁴⁴ used improved dosing instructions as a part of their intervention which resulted in better medication adherence. Odegard and Gray² conducted their study on poorly controlled diabetes patients and listed “ability to read prescription labels” as one barrier for medication adherence among paying for medications, remembering doses and obtaining refills.² Wolf et al³¹ used a patient-centered drug label strategy to find that there were significant benefits to medication adherence among patients with limited literacy. These data clearly indicate that medication adherence is a complex, multifactorial issue and other unaddressed or unknown factors may have affected the result of the foregoing studies.

A few important gaps were identified on the practice of writing dosing instructions and related research. One important observation was that pharmacists in general do not appear to use a standard set of guidelines when providing medicines information. A universal approach and format on writing dosing instructions, taking into consideration the abovementioned findings, would be immensely helpful in the provision of complete, consistent and comprehendible instructions to patients. Most medicine labels are hand-written, especially in the South East Asian countries, but not many studies have assessed the legibility of dosing instructions written by pharmacists. Given the issues related to illegible prescriptions, legibility of hand-written dosing instructions is undoubtedly a problem worth further study. Finally, except for a very few studies,⁴⁵ most workers have used mock dispensing labels and artificial situations to assess the readability and comprehensibility of dosing instructions. There is a need, therefore, for more research that measure the readability and comprehensibility of information related to patients’ own medications in real life.

There are some limitations in this communication that needs to be acknowledged by the readers. Articles used in this narrative review were not obtained using a systematic process. We used only PubMed, SAGE and Google Scholar to extract our findings, hence there is a chance that some relevant studies not indexed in these search engines may have been missed. A critical appraisal of articles was not performed using a formal checklist, but reviewers used self-judgment to appraise the studies before selection. However, we have taken care to present an unbiased view of the studies accessible through the method we used.

Conclusion

To conclude then, providing clear, readable and comprehensible prescription labels is a crucial and a key role of the pharmacist. Our review highlights key factors that need to be considered when writing dispensing labels, such as patient literacy levels, age, number of medicines dispensed, format and organization of the medicines label, complexity of dosing instructions, precision of writing dosing instructions and the use of icons, graphics and pictograms when writing prescription labels. We also emphasize do’s and don’ts related to such key factors as lessons for pharmacists when writing dispensing labels. There is a surprising lack of standardization when writing dosing instructions to the public by pharmacists, and hence propose the need for universal guidelines.

Disclosure

The authors report no conflicts of interest in this work.

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