Analogous comparison of registered brand name drugs of tablets and capsules commercially available in Thailand: A retrospective study.

Drug name confusion or similar product packaging and labeling, also known as "look-alike, sound-alike" (LASA) medication error, is one of the most problematic causes of prescribing and dispensing errors. Therefore, this study aimed to compare the similarity of registered brand name drugs of tablets and capsules that are commercially available in Thailand to estimate the magnitude of LASA medication errors. Analogous comparisons of brand names using similarity in orthography (written forms with identical letters) were analyzed retrospectively. Tablets and capsules commercially available in Thailand and registered with the Bureau of Drug Administration, Food and Drug Administration (FDA) in 2012 as "dangerous drugs" and "specially controlled drugs" for humans and animals were included in this study. Descriptive statistics, including frequencies and percentages, were used in this study. The analogous comparison of brand name orthography was scrutinized, and the results revealed 1,668 brand names, which were categorized into three genres as follows: 1) Single brand names from a single manufacturer having the same active pharmaceutical ingredient (API) with numerous registration numbers (1,049 names, 62.89% of the total similarity results) 2) Single brand names from different manufacturers having the same API and possessing several registration numbers (615 names, 36.87% of the total similarity results) 3) Single brand names from different manufacturers with diverse APIs (four brand names, 0.24% of the total similarity results). Analogous results revealed that numerous identical brand names could be derived from the same manufacturers, APIs, dosage strengths, or otherwise. The results of this study recommend improvement on product registration to better ensure patient safety in the future.