Poor quality and variability of medication labeling have been cited as key contributors to medication misuse. Evidence suggests that health literacy plays a significant role in determining how well patients interpret medication labels and take nonprescription and prescription drugs safely and appropriately. Research aimed at improving medication labeling is described below.
A study published in 2013external iconexternal icon finds a patient-centered label was better at preventing participants from exceeding the maximum dose in 24 hours, compared to a standard label. The patient-centered label did not significantly reduce other dosing errors such as taking more than two pills at a time and waiting fewer than four hours between doses.
A study investigating how parents use active ingredient informationexternal iconexternal icon found many parents, especially those with low health literacy, do not use active ingredient information as part of decision-making related to administering multiple medications. Overlapping active ingredients across multiple medications put children at risk for overdose.
A 2012 reviewexternal iconexternal icon of 200 top-selling pediatric oral liquid nonprescription medications found that labeling was often variable and in a format that may impair parent understanding of key medication information, including active ingredient information and dosing instructions. Although most products listed active ingredients on the Drug Facts panel, 18.5% did not list active ingredients on the principal display panel. Most products included directions in chart form, while few products expressed dosing instructions in pictographic form.
In a 2011 studyexternal iconexternal icon, less than 50% of focus group participants reported routinely examining product label information. Only 31% were aware that acetaminophen is in Tylenol. Participants achieved consensus on an icon to identify products that contain acetaminophen, a written statement warning of potential liver damage, and indicated a preference for an icon and wording for maximum daily dose.
Medication instructions are often the most tangible, frequently used source of information for patients on proper medication use. However, they are often vague and unnecessarily complex. Several studies explore how to improve patients’ comprehension of safe and appropriate medication use.
Medication guides were assessed by Wolf et al 2012external iconexternal icon to determine their effectiveness in adequately informing patients on safe use. Current medication guides were found to be of little value to patients, as they are too complex and difficult to understand especially for individuals with limited literacy. In a follow-up studyexternal iconexternal icon, the format and layout of three typical medication guides were modified to promote information accessibility. Comprehension was significantly greater for all three prototypes compared with the current standard, and the guide modified according to health literacy best practices consistently demonstrated the highest scores, and reduced the effects of age and literacy disparities.
Patient preferences for how best to display patient medication information (PMI) were assessed in a study published in 2014external iconexternal icon. Similar to the Food and Drug Administration’s medication guides, PMI handouts are intended to help all consumers understand key information about their prescription medicine. Participants in one-on-one interviews noted their preference for new PMI handouts over existing medication guides or consumer medication information. Although many preferences varied by age, education, and health status, most preferred to see drug information in a chunked format that is printed in a sans serif font, such as Arial.
Patient opinions, preferences and comprehension of standard and improved medication instructions were assessed in a 2013 studyexternal iconexternal icon. Patients agreed on the need for simpler terminology and specificity in instructions. Discussions addressed optimal ways of presenting numerical information, and indication and duration of use information to promote comprehension and safe use.
In a study published in 2012external iconexternal icon, limited English proficient (LEP) patients receiving prescription medication instructions in their native language demonstrated significantly greater prescription understanding in comparison to those receiving standard instructions. In most cases, instruction type was the sole, independent predictor of greater prescription understanding and demonstrated ability to correctly dose multiple prescriptions in multivariate models controlling for relevant covariates.
Results from a study published in 2011external iconexternal icon show the benefit of including pictographic dosing diagrams as part of written medication instructions for infant acetaminophen. Parents receiving text-plus-pictogram instructions had higher dosing accuracy than parents receiving standard text-only instructions. These differences were observed among parents with low health literacy, but not for parents with adequate health literacy.
Greater regimen complexity may lead to poorer adherence, which in turn will lead to worse health outcomes. How patients manage their medication regimens, and the role health literacy plays, are explored in the studies described below.
Lenahan et al 2013external iconexternal icon investigated drug regimen familiarity among a cohort of patients with hypertension. Specifically, the authors determined the prevalence of patients’ knowledge of their prescribed drug names and dosages compared to those who relied only on physical characteristics such as pill size, shape and color. Patients dependent on the visual identification of their medicine reported worse adherence, lower rates of blood pressure control and greater risk of hospitalization.
A study published in 2013external iconexternal icon explores the relationship between functional health literacy, medication-taking self-efficacy, and adherence to HIV/AIDS antiretroviral therapy. Functional health literacy was not significantly related to either medication adherence or self-efficacy beliefs. The authors suggest their measurement strategy as a possible explanation for this unexpected finding.
Wolf et al 2011external iconexternal icon investigate how well patients manage complex medication regimens that require them to consolidate dosing schedules throughout the day. The finding that many patients, especially those with limited literacy, do not consolidate regimens efficiently supports the Institute of Medicine’s proposal of a universal medication schedule to standardize prescription practices to improve medication adherence.