Publications by authors named "Kamonthip Wiwattanawongsa"

CYP3A4-mediated metabolic conversion of mitragynine to 7-hydroxymitragynine (7OH) has been demonstrated in human liver microsomes, and in rodents. Pharmacokinetics (PK) of mitragynine and 7OH in humans is still limited. We aimed to examine the pharmacokinetics of mitragynine and the formation of 7OH in healthy volunteers.

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Background: The appropriate dose of gentamicin is important to prevent and treat infections. The study aimed to determine the optimal dose of gentamicin to achieve the probability of pharmacokinetic/pharmacodynamic (PK) targets for efficacy and safety in multiple trauma patients.

Methods: PK parameters of gentamicin in multiple trauma patients were gathered to develop a one-compartment PK model for prediction.

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Background: In addition to the maximum plasma concentration (C) to the minimum inhibitory concentration (MIC) ratio, the 24-hour area under the concentration-time curve (AUC) to MIC has recently been suggested as pharmacokinetic/pharmacodynamic (PK/PD) targets for efficacy and safety in once-daily dosing of gentamicin (ODDG) in critically ill patients.

Purpose: This study aimed to predict the optimal effective dose and risk of nephrotoxicity for gentamicin in critically ill patients for two different PK/PD targets within the first 3 days of infection.

Methods: The gathered pharmacokinetic and demographic data in critically ill patients from 21 previously published studies were used to build a one-compartment pharmacokinetic model.

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Both quercetin and resveratrol are promising plant-derived compounds with various well-described biological activities; however, they are categorized as having low aqueous solubility and labile natural compounds. The purpose of the present study was to propose a drug delivery system to enhance the oral bioavailability of combined quercetin and resveratrol. The suitable self-microemulsifying formulation containing quercetin together with resveratrol comprised 100 mg Capryol 90, 700 mg Cremophor EL, 200 mg Labrasol, 20 mg quercetin, and 20 mg resveratrol, which gave a particle size of 16.

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A supersaturatable self-microemulsifying drug delivery system (S-SMEDDS) with a reduced amount of surfactant and incorporation of a polymer precipitation inhibitor, Eudragit® E PO was developed. The optimized S-SMEDDS formulation (SS-15) consisted of 55% surfactants, 40% oils, and 5% Eudragit® E PO (curcumin at 44.4 mg/g of the formulation).

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The use of curcumin and resveratrol in combination has now become increasingly of interest because of their synergistic effects as therapeutic agents for various diseases, especially cancer. To overcome the poor oral bioavailability of both compounds and improve patient compliance, a novel self-microemulsifying formulation containing curcumin together with resveratrol was developed. Capryol 90, Cremophor EL, and Labrasol were selected as the oil, surfactant, and co-surfactant in the formulation, respectively, based on the solubility study of both compounds.

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Self-microemulsifying drug delivery systems (SMEDDS) containing two types (Tween80 and Labrasol) and two levels (low; 5% and high; 15%) of co-surfactants were formulated to evaluate the impact of surfactant phase on physical properties and oral absorption of oxyresveratrol (OXY). All formulations showed a very rapid release in the simulated gastric fluid (SGF) pH 1.2.

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The aim of this study was to develop and assess nanostructured lipid carriers (NLC) compared to solid lipid nanoparticles (SLN) for improving the oral bioavailability of oxyresveratrol (OXY). The OXY formulated as SLN (OXY-SLN) and NLC (OXY-NLC) were prepared by a high shear homogenization technique. The optimized OXY-NLC (NLC3) produced smaller nanoparticle sizes (96±0.

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Novel self-microemulsifying floating tablets were developed to enhance the dissolution and oral absorption of the poorly water-soluble tetrahydrocurcumin (THC). Their physicochemical properties and THC permeability across Caco-2 cell monolayers were assessed. The self-microemulsifying liquid containing THC was adsorbed onto colloidal silicon dioxide, mixed with HPMC, gas-generating agents (sodium bicarbonate and tartaric acid), lactose and silicified-microcrystalline cellulose and transformed into tablets by direct compression.

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The objective of this study was to determine the pharmacokinetics and dosing recommendations of vancomycin in critically ill patients receiving continuous venovenous haemofiltration (CVVH). A prospective study was conducted in the Intensive Care Unit of a university hospital. Seven patients receiving CVVH with a triacetate hollow-fibre dialyser were enrolled.

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Purpose: A series of ester derivatives of mefenamic acid were synthesized with the aim of suppressing local gastrointestinal toxicity of mefenamic acid. A computational method was used to assist the design of the prodrug and to gain insights into the structure relationship of these compounds as P-glycoprotein (P-gp) substrates. The prodrugs were studied for their enzymatic stability, bidirectional permeability across Caco-2 monolayer, and their potential as transporter modulators

Methods: Bidirectional transport studies were performed using Caco-2 cells.

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The objective of this study was to investigate the effect of concurrent antibiotic administration on the disposition of mycophenolic acid (MPA) and mycophenolic acid glucuronide (MPAG) after oral administration of mycophenolate mofetil (MMF) in healthy subjects. Eleven healthy subjects were enrolled. The study was divided into 4 treatment periods.

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A novel technique based on Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy was used to study the transport of benzoic acid ion-pairs/salts in silicone membranes. The benzoic acid ion-pairs were prepared using various counter-ions with different degrees of lipophilicity, e.g.

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Purpose: Prodrug of non-steroidal anti-inflammatory drugs (NSAIDs) or NSAIDs linked with guaiacol have been reported to suppress gastrointestinal (GI) toxicity or induce GI protective effect. In this study. mefenamic-guaiacol ester was synthesized and its physicochemical properties.

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