1. Introduction
At least 1.5 million preventable adverse drug events (ADE) occur each year in the U.S. [22]. Medication errors related to ADEs can occur while writing or filling prescriptions, or even when taking or managing medications [1]. For example, pharmacists must verify thousands of pills dispensed daily in the pharmacy, a process that is largely manual and prone to error. Chronically-ill and elderly patients often separate pills from their original prescription bottles, which can lead to confusion and misadministration. Many errors are preventable; however, pills with visually similar characteristics are difficult to identify or distinguish, increasing error potential.