FDA List of Established Drug Names Recommended to Use Tall Man Lettering (TML)

Tall man lettering (TML) is a technique that uses uppercase lettering to help differentiate look-alike drug names.  Starting on the left side of a drug name, TML highlights the differences between similar drug names by capitalizing dissimilar letters (e.g., vinBLAStine versus vinCRIStine and CISplatin versus CARBOplatin).¹  TML can be used along with color or bolding to draw attention to the dissimilarities between look-alike drug names, and alert healthcare providers that the drug name can be confused with another drug name.

In 2001, FDA initiated the name differentiation project to continually evaluate postmarketing reports of name pair confusion, and  determine if TML should be used to help differentiate similar established names.   The FDA evaluation considers multiple factors, including the degree of similarity between the name pair, safety risks with confusion between the name pair, overlapping product characteristics, reports of wrong drug errors, and causes or contributing factors.  If FDA’s evaluation determines TML is an appropriate approach to address reports of name confusion, FDA will request the manufacturer voluntarily revise their labels and labeling to use TML, and then update the FDA List of Established Drug Names Recommended to Use Tall Man Lettering.  FDA may also consider labeling revisions, safety communications, and other approaches to address reports of product name confusion.

¹Institute for Safe Medication Practices. Special edition: tall man lettering; ISMP updates its list of drug names with tall man letters.  2016 Jun 2 [cited 2019 Aug 23].

The following is a list of the established drug names recommended to use tall man lettering:

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