“We need to figure out which are the most important warnings and only put those on the label. Otherwise you risk the message never reaching the patient,” Michael Wolf stresses. “The more warnings you put on a label, the more you distract them from essential instructions and precautions that ensure they safely use the medicine.”

NORTHWESTERN (US)—Warnings on prescription labels should be clear, concise—and in short supply—to be the most effective, new research finds.

“The study shows the value of a clear message,” says the study’s lead author Michael Wolf, associate professor of medicine and of learning sciences at the Feinberg School of Medicine at Northwestern University.

“A lot of the current warnings were phrased very abstractly and were confusing. For example, we changed ‘For external use only’ to ‘Use only on your skin.’ We moved from the intangible to the concise.”

For the study, researchers worked with patients and graphic designers to simplify and redesign the confusing language and icons of standard warning labels, many of which have been used for decades without any evidence to show that patients comprehend them, or even if they are true, Wolf says.

Half of adults misunderstand common standard drug warnings on prescription labels, putting them at risk for using the medicine incorrectly or even having a life-threatening event.

Further, the study found that patients with low health literacy, the group at greatest risk for misinterpreting instructions and misusing medication, benefit greatly from newly designed icons which improve understanding.

Findings were published in a recent issue of Archives of Internal Medicine.

The graphic designers worked with researchers and patients to capture their mental images of what each message means. For example, “A current and widely used icon of a pregnant woman resembles an olive,” Wolf says.

“For most people that probably doesn’t convey pregnancy. The new design of a silhouette of a pregnant woman with a bump on her stomach was more easily recognizable to patients.”

The study tested 500 adult patients from two academic and two community health clinics in Chicago and Shreveport, La., on their interpretation of nine drug warning labels.

The labels were current standard drug warning labels on prescription containers; drug warnings with text rewritten in simplified language or labels with simplified language and icons developed with patient feedback.

The patients reading standard labels had an 80 percent rate of correct interpretations, simplified text was 91 percent and simplified text with new icons was 92 percent.

The study maintains that bottle warnings should be few in number and up-to-date. “There may not be a reason to use many of these” that were created years ago with no scientific basis, Wolf notes.

“And with such limited real estate on a pill bottle, the fewer the better. Our study supports that.

“We need to figure out which are the most important warnings and only put those on the label.  Otherwise you risk the message never reaching the patient,” Wolf stresses. “The more warnings you put on a label, the more you distract them from essential instructions and precautions that ensure they safely use the medicine.”

Wolf and colleagues from Emory, Harvard and Louisiana State universities are currently working with the U.S. Pharmacopeia on a drug labeling task force to help overhaul the content and use of these labels.

The study was funded by Target Corp. and the Agency for Healthcare Research and Quality.

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