Levothyroxine (LT4), being "narrow therapeutic index" drug, may lead to significant fluctuations in thyroid stimulating hormone (TSH) levels. Such fluctuations can result in clinically noteworthy disruptions in thyroid function and give rise to adverse clinical consequences. Consequently, regulatory standards for LT4 potency have been tightened, with the most stringent specifications requiring maintenance of potency within the range of 95-105% of the labeled dose throughout the entire shelf-life of the product. The LT4 new formulation with tightened specification adheres to these rigorous standards, demonstrating established bioequivalence to its older formulation while upholding an equivalent standard of safety and efficacy. Furthermore, the novel formulation exhibits enhanced stability and an extended shelf-life. Of paramount significance is its capacity to provide patients with accurate and consistent dosing, thereby effectively catering to their medical requirements. The primary objective of the Asia-Pacific advisory board meeting (held in June 2022 with endocrinologists, experts from India, Indonesia, Philippines, Thailand, Malaysia and Singapore) was to establish the importance of appropriate communication to HCPs, patients and other stakeholders regarding the LT4 new formulation. The aim of this brief review is to highlight the importance of communication with healthcare professionals that should focus on providing accurate information on the LT4 new formulation, emphasizing efficacy, safety, and bioequivalence with clear guidance and ensure that patients and clinicians are fully informed about any changes to medications such as LT4 to reduce the risk of unrelated adverse events being incorrectly attributed to the newer formulation.
The abuse of phenylbutazone among rheumatoid arthritis patients has recently become a subject of interest. Unscrupulous manufacturers take advantage of the miraculous analgesic property of phenylbutazone and deliberately add this toxic drug in their preparations without declaring its presence on the label. In a recent survey, many such illicit preparations were seized from Chinese medical halls in Johor and sent to the Department of Chemistry, Johor Bahru for analysis. Here a Gas Chromatograph Mass Selective Detector (GC-MSD) method was developed for the determination of phenylbutazone in illicit traditional preparations.