Levothyroxine (T4) is a narrow therapeutic index drug with classic bioequivalence problem between various available products. Dissolution of a drug is a crucial step in its oral absorption and bioavailability. The dissolution of T4 from three commercial solid oral dosage forms: Synthroid (SYN), generic levothyroxine sodium by Sandoz Inc. (GEN) and Tirosint (TIR) was studied using a sensitive ICP-MS assay. All the three products showed variable and pH-dependent dissolution behaviors. The absence of surfactant from the dissolution media decreased the percent T4 dissolved for all the three products by 26-95% (at 30 min). SYN dissolution showed the most pH dependency, whereas GEN and TIR showed the fastest and highest dissolution, respectively. TIR was the most consistent one, and was minimally affected by pH and/or by the presence of surfactant. Furthermore, dissolution of T4 decreased considerably with increase in the pH, which suggests a possible physical interaction in patients concurrently on T4 and gastric pH altering drugs, such as proton pump inhibitors. Variable dissolution of T4 products can, therefore, impact the oral absorption and bioavailability of T4 and may result in bioequivalence problems between various available products.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.ejpb.2008.10.008 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Probing the Interaction Mechanisms of Dodecane and Mica/Calcite: Implications for Oil Recovery.
Langmuir
January 2025
School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, P. R. China.
Understanding the interfacial interaction mechanisms between oil and minerals is of vital importance in the applications of petroleum production and environmental protection. In this work, the interactions of dodecane with mica and calcite in aqueous media were investigated by using the drop probe technique based on atomic force microscopy. For the dodecane-mica interactions, the electrical double layer (EDL) repulsion dominated in 10 mM NaCl solution, and a higher pH facilitated the detachment of dodecane.
View Article and Find Full Text PDFCannabidiol and Hydroxypropyl-β-Cyclodextrin for the Development of Deflated Spherical-Shaped Inhalable Powder.
AAPS J
January 2025
Laboratory of Pharmaceutical Technology and Biopharmacy, CIRM, University of Liège, 4000, Liège, Belgium.
In addition to the known therapeutic indications for cannabidiol, its administration by inhalation appears to be of great interest. Indeed, there is evidence of cannabidiol's efficacy in several physiological pathways, suggesting its potential for a wide range of applications for both local and systemic pulmonary administration like cancers. Significant advances in pulmonary drug delivery have led to innovative strategies to address the challenges of increasing the respirable fraction of drugs and standardizing inhalable products.
View Article and Find Full Text PDFManipulating Charge Distribution at Organic-inorganic Interface via Optimizing Substituents for Sustainable Water Electrolysis.
Angew Chem Int Ed Engl
January 2025
Anhui Normal University, School of Chemistry and Materials Science, CHINA.
The space charge effect induced by high-quality heterojunctions is essential for efficient electrocatalytic processes. Herein, we delicately manipulate intermolecular charge transfer by modifying substituents (-g = -CH3, -H, -NO2) with various electron donating/withdrawing capabilities in CoPc-g/CoS organic-inorganic heterostructures. CoPc-CH3, as a typical electron donor, transfers more electrons to CoS due to the presence of -CH3, forming the strongest space electric field and thus regulating the dual active sites at the interface.
View Article and Find Full Text PDFEffective pretreatment of tea stem via poly-deep eutectic solvent for promoting platform molecule production and obtaining fluorescent lignin.
Int J Biol Macromol
January 2025
College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, China; Fujian Provincial Key Laboratory of Food Microbiology and Enzyme Engineering, Xiamen 361021, China; Research center of food biotechnology of Xiamen city, Xiamen, Fujian 361021, China. Electronic address:
In this study, polyethylene glycol 200 (PEG200) was employed as hydrogen bond acceptor, while organic acids served as hydrogen bond donors, to formulate poly-deep eutectic solvents (PDESs), which were utilized to pretreat tea stem. Specially, combining PEG200 and oxalic acid (OA) exhibited a notably high cellulose retention (82.03 %) and most efficient hemicellulose (97.
View Article and Find Full Text PDFCharacterisation of the submarine disposal of a Bayer effluent (Gardanne alumina plant, southern France): III: Trace metals in the seawater column in the vicinity of the discharge area in the Mediterranean Sea.
Mar Pollut Bull
January 2025
CREOCEAN, Valparc- bât B, 230 avenue de Rome, 83500 La Seyne-sur-Mer, France.
In the context of evaluating the environmental impact of deep-sea tailing practices, we conducted a case study on the Bayer effluent released into the Mediterranean Sea by the French Gardanne alumina plant. This effluent results from the filtration of red mud, which has previously been discharged into the Cassidaigne canyon for 55 years. In 2015, regulatory changes permitted the released of a filtered effluent instead of the slurry.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!