Tall man letters are utilized for drugs that:

Tall man letters are a specific typographical technique used to differentiate between look-alike drug names, helping to reduce medication errors. This method involves capitalizing certain letters in the names of medications that may be easily confused with one another, thereby drawing attention to the differences. For example, the medications "Morphine" and "Hydromorphone" may be presented as "MORPHINE" and "HYDROmorphone" to avoid mix-ups.

This practice is particularly important in preventing medication errors that can occur in pharmacies and healthcare settings, where the visual similarity of drug names can lead to dangerous mistakes when prescribing or dispensing medications. The use of tall man letters is a well-accepted strategy within the pharmaceutical industry and is often recommended by organizations focused on medication safety.

While prescription drugs, controlled substances, and those with high misuse potential are all serious concerns, they are not specifically related to the purpose of tall man letters, which is aimed explicitly at improving clarity in drug names that look alike.