Prescription errors. Legibility and drug name confusion.

Inadvertent drug substitution occurred in several instances in our practices due to the combination of the physician's illegible handwriting on prescriptions and the pharmacist's misinterpretation of subtle clues, which might have prevented the errors. The literature on the legibility of physician handwriting is reviewed. Our specific recommendations include using preprinted prescription pads, training staff assistants who write prescriptions, printing complete directions on each prescription, and aggressively educating each patient about the name and purpose of all drugs being prescribed. Patients are encouraged to bring their medications to each office visit to identify potential errors.