Liquid levothyroxine and its potential use.

Traditionally, L-T4 has been available in tablet form as a stable salt that contains sodium; approximately 6090 % of the dose is absorbed in the jejunum and ileum within 3 hours of ingestion.6 Absorption is maximal when it is taken on an empty stomach, demonstrating the importance of gastric acidity in the process. In fact, the acid gastric pH is essential to dissolve the tablet, removing sodium ion and converting L-T4 into a lipophilic molecule.7 Recently, novel formulations of L-T4, such as soft gel capsule and liquid form, have been made available. This review will focus on liquid L-T4 formulation and its potential benefit.