Tall Man Lettering

USP�s Drug Error Finder site allows healthcare workers or patients to type in a drug name to see if it has the potential to be confused with other medications. (click image to enlarge)

Recently, organizations keeping a vigil on prescription drug safety have focused on distinguishing between look-alike or sound-alike drug names. Tall Man lettering, meaning uppercase letters within a drug name used to highlight its differentiating letters, has come out as a key option.

The National Association of Boards of Pharmacy (NABP) passed a resolution that Tall Man letters be used for look-alike or sound-alike drug names. The resolution states that the NABP will work with FDA and United States Pharmacopeia (USP) to propose this lettering on labels. The resolution also states the group will work with suppliers of pharmacy data systems and software to recognize Tall Man lettering.

The involvement of USP came after the group released a study called the Medication Errors Reporting Program (MERP), a joint venture between USP and the Institute for Safe Medication Practices (ISMP). This voluntary reporting program accepted confidential reports on errors such as mixing up look-alike or sound-alike drugs. With the results, the USP developed a Web-based tool for healthcare professionals and the public to see whether the drugs they take or prescribe use commonly confused sound-alike drugs, and what drugs might be confused with them (www.usp.org/hqi/similarProducts/choosy.html).

Earlier investigation into the use of Tall Man lettering occurred with FDA’s Name Differentiation Project in 2001, in which drug makers voluntarily revised the look of 16 established name pairs to minimize medication errors from look-alike confusion. After the two-month project, undertaken by the Center for Drug Evaluation and Research’s Office of Generic Drugs, 142 letters for 159 applications were issued encouraging manufacturers to supplement applications with revised labels and labeling that visually differentiated their names with Tall Man letters.

A ISMP study last summer polled healthcare providers on their experience with the need for drug name differentiation. Respondents cited the use of Tall Man letters as their first choice for distinguishing between look-alike or sound-alike names, with the majority saying such letters reduce the similarity between names. A high percentage (87%) felt the medical product industry’s use of Tall Man letters helps to reduce drug selection errors, and two-thirds (64%) said Tall Man lettering stopped them from dispensing or administering the wrong medication.

Tall Man letters would replace lower-case letters in drug names where similarities to other drugs is evident. ISMP survey respondents pointed out several cases where Tall Man lettering could help. Three-quarters (76-77%) of respondents agreed to the survey suggestion that the names NovoLOG and NovoLIN, HumaLOG and HumuLIN, benefited from the lettering change. About two-thirds (60-66%) of respondents agreed to the similar suggestion for oxyCODONE and OxyCONTIN, ceFAZolin and cefTRIAXONE, and FLUoxetine and DULOXetine. One drug name pair in the survey received a vote of less than effective from half of the respondents: clonazePAM and LORazePAM.