• Archives of Pharmacal Research
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• v.28 no.4
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• pp.488-492
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• 2005

The purpose of this study is to investigate the bioequivalence of two haloperidol 5 mg tablets, Myung In haloperidol (Myung In Pharm. Co., Ltd., test drug) and $Peridol^{R}$(Whanin Pharm. Co., Ltd., reference drug), and also to estimate the pharmacokinetic parameters of haloperidol in Korean volunteers. The bioavailability and pharmacokinetics of haloperidol tablets were examined on 24 healthy volunteers who received a single oral dose of each preparation in the fasting state in a randomized balanced 2 way crossover design. After an oral dosing, blood samples were collected for a period of 60 h. Plasma concentrations of haloperidol were determined using a liquid chromatographic electrospray mass spectrometric (LC-MS) method. The pharmacokinetic parameters were calculated with noncompartmental pharmacokinetic analysis. The geometric means of $AUC_{0-60h} and C_{max}$ between test and reference formulations were $17.21\pm8.26 ng\cdot/mL vs 17.31\pm13.24 ng\cdot/mL and 0.87\pm0.74 ng/mL vs 0.85\pm0.62 ng/mL$. respectively. The $90\%$ confidence intervals of mean difference of logarithmic transformed $AUC_{0-60h} and C_{max} were log0.9677{\sim}log1.1201 and log0.8208{\sim}log1.1981$, respectively. It shows that the bioavailability of test drug is equivalent with that of reference drug. The geometric means of other pharmacokinetic parameters ($AUC_{inf}. t_{1/2}, V_{d}/F, and CL/F$) between test drug and reference drug were $21.75\pm8.50 ng{\cdot}h/mL vs 21.77\pm15.63 ng{\cdot}h/mL, 29.87\pm8.25 h vs 29.60\pm7.56 h, 11.51\pm5.45 L vs 12.90\pm6.12 L and 0.26\pm0.09 L/h vs 0.31\pm0.17 L/h$, respectively. These observations indicate that the two formulation for haloperidol was bioequivalent and, thus, may be clinically interchangeable.

• Journal of Ginseng Research
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• v.43 no.3
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• pp.354-360
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• 2019

Ginsenosides, the major active ingredients of ginseng and other plants of the genus Panax, have been used as natural medicines in the East for a long time; in addition, their popularity in the West has increased owing to their various beneficial pharmacological effects. There is therefore a wealth of literature regarding the pharmacological effects of ginsenosides. In contrast, there are few comprehensive studies that investigate their pharmacokinetic behaviors. This is because ginseng contains the complicated mixture of herbal materials as well as thousands of constituents with complex chemical properties, and ginsenosides undergo multiple biotransformation processes after administration. This is a significant issue as pharmacokinetic studies provide crucial data regarding the efficacy and safety of compounds. Moreover, there have been many difficulties in the development of the optimal dosage regimens of ginsenosides and the evaluation of their interactions with other drugs. Therefore, this review details the pharmacokinetic properties and profiles of ginsenosides determined in various animal models administered through different routes of administration. Such information is valuable for designing specialized delivery systems and determining optimal dosing strategies for ginsenosides.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.207-214
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• 2008

In recent years, the combined use of Herbal medicines and Western drugs has been increasing. Though certain problems may occur when both types of medicines are taken together, they havenot been adequately analyzed. It was reported that anticoagulation was enhanced in addition tobleeding when patients took long-term warfarin therapy in combination with Salvia miltiorrhiza(danshen), and laxative herbs accelerate intestinal transit and interfere with the absorption. Herbal constituents, curcumin, ginsenosides, piperine, catechins and silymarin were found to beinhibitors of P-glycoprotein. St John's wort induces the intestinal expression of P-glycoprotein. Anthraquinone, quercetin and coumarins were found to be a potent inhibitor of P-450. Glycyrrhizin or liquorice extracts, Garlic and St John's wort are a potent inducer of CYP3A4. This review provides a critical overview of interactions between herbal medicines and other drugs. Hence, it is necessary to study the pharmacodynamic and pharmacokinetic interactions of many herbal medicines between western drugs.

• Journal of Biomedical Engineering Research
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• v.24 no.1
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• pp.45-53
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• 2003

Based on the 4-compartmental pharmacokinetic model developed in PART1, target-controlled infusion(TCI) pump system was designed and evaluated. The TCI system consists of digital board including microcontroller and digital signal process(DSP), analog board, motor-driven actuator, user friendly interface, power management and controller. It provides two modes according to the drugs: plasma target concentration and effect target concentration. Anaesthetist controls the depth of anaesthesia for patients by adjusting the required concentration to maintain both plasma and effect site in drug concentration. The data estimated in DSP include infusion rate, initial load dose, and rotation number of motor encoder. During TCI operation, plasma concentration. effect site concentration, awaken concentration, context-sensitive decrement time and system error information are displayed in real time. Li-ion battery guarantees above 2 hours without power line failure. For high reliability of the system, two microprocessors were used to perform independent functions for both pharmacokinetic algorithm and motor control strategy.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.10a
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• pp.135-136
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• 1995

Resent advances in computer technology have introduced a sophisticated capability for computing the biological fate of toxicants in a biological system. This methodology, which has drastically altered risk assessment skill in toxicology, is designed using all the mechanistic information, and all claim better accuracy with extrapolating capability Iron animal to people than conventional pharmacokinetic methods. Biologically based mathematical models in which the specific mechanistic steps governing tissue disposition(pharmacokinetics) and toxic action (pharmacodynamics) of chemicals are constructed in quantitative terms by a set of equations loading to prediction of the outcome of specific toxicological experiments by computer simulation. pharmacokinetic and pharmacodynamic models are useful in risk assessment because their mechanistic biological basis permits the high-to-low dose, route to route and interspecies extrapolation of the tissue disposition and toxic action of chemicals.

• The Korean Journal of Applied Statistics
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• v.25 no.1
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• pp.139-152
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• 2012

The result of the analysis of a population pharmacokinetic model can directly influence the decision of the dose level applied to the targeted patients. Therefore the validation procedure of the final model is very important in this area. This paper reviews the validation methods of population pharmacokinetic models from a statistical viewpoint. In addition, the whole procedure of the analysis of population pharmacokinetics, from the base model to the final model (that includes various validation procedures for the final model) is tested with real clinical data.

• Journal of Pharmaceutical Investigation
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• v.39 no.5
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• pp.373-379
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• 2009

This study was conducted to develop a pharmacokinetic-pharmacodynamic (PK/PD) model of a direct thrombin inhibitor, argatroban to predict the concentration-effect profiles in rats. Argatroban was i.v. injected to rats at 0. 2, 0.8 and 3.2 mg/kg doses (n = 4-5 per dose), and plasma drug levels were determined by a validated LC/MS/MS assay. The pharmacokinetics of argatroban was linear over the i.v. dose range studied. The thrombin time (TT) and the activated partial thromboplastin time (aPTT) were measured in rat plasma and they were found to linearly increase with increasing the dose. A 2-compartment pharmacokinetic model linked with an indirect response pharmacodynamic model was successfully utilized to evaluate the drug concentration-response relationship.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.664-669
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• 2001

Acebutolol is almost absorbed after oral administration, but its bioavailability is reduced because of considerable first-pass metabolism through the gastrointestinal tract and liver. The purpose of this study was to report the pharmacokinetic changes of acebutolol (15 mg/kg,oral) and its main metabolite, diacetolol in rabbits pretreated (15 mg/kg, oral) and coadministered (15 mg/kg, S. C., bid for 3 days) with diltiazem. The plasma concentration and area under the plasma concentration-time curves (AUC) of acebutolol and diacetolol were significantly increased in rabbits pretreated and coadministered with diltazem. The elimination rate constant ( $K_{el}$ ) and total body clearances (CL $_{t}$) of acebutolol and diacetolol were significantly decreased and half-life of those were significantly prolonged in the rabbit. Metabolite percentage rate of diacetolol to the plasma concentration of total acebutolol in rabbits pretreated and coadministered with diltiazem were significantly decreased. The results suggest that the dosage of acebutolol should be adjusted when the drug would be administered chronically with diltiazem in a clinical situation.n.

• YAKHAK HOEJI
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• v.34 no.1
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• pp.40-46
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• 1990

Pharmacokinetic studies on praziquantel in rabbits were performed in this paper. The pharmacologically active parent drug was separated from the pharmacologically inactive metabolites by HPLC method. The pharmacokinetic parameters of parent drug were obtained. In vitro partition to blood cells of praziquantel was measured. The mean value (n = 3) of partition to blood cells was 44% at concentrations between $1\;{\mu}g/ml$ and $40\;{\mu}g/ml$. Therefore, the relatively high partition to blood cells should be considered in further pharmacokinetic studies on praziquantel.

• YAKHAK HOEJI
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• v.57 no.6
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• pp.442-447
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• 2013

The aim of the present study was to improve commercial twice-a-day Acebrophylline formulation to once-a-day new formulation to improve patient compliances. To develop the double-layered tablet, the sustained release layer was prepared using Eudragit$^{(R)}$ L100-55 and Carnauba wax. The sustained release layer has shown delayed release rates in pH 1.2 which comparable to that of performed in pH 6.8 buffer. In the comparative pharmacokinetic study with commercialized Surfolase$^{(R)}$, the present double-layered Acebrophylline tablet has shown similar pharmacokinetic parameters of AUC, $C_{max}$ and $T_{max}$ values.