• Toxicological Research
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• v.21 no.4
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• pp.319-323
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• 2005

The aim of the present study was to evaluate systemic bioavailability of surfactin and to determine its pharmacokinetic profiles. The stability of surfactin to pH, temperature and protease was evaluated. Surfactin was resistant to high temperature, a wide range of pH and the action of hydrolytic enzymes. The pharmacokinetic natures of surfactin which were shown the short half-life, rapid clearance and poor bioavailability. The results of study should provide preliminary data of surfactin for further dose-finding studies and for the design of application forms. It is also be important to a context of the safety of surfactin.

• YAKHAK HOEJI
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• v.30 no.6
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• pp.288-293
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• 1986

Effects of phenobarbital on the pharmacokinetics of griseofulvin were studied in rats. Phenobarbital was administered orally for five days at the dose of 75mg/kg/day. Absolute bioavailability of oral griseofulvin was significantly(p<0.005) reduced but total clearance(CL$_s$ was not changed by phenobarbital pretreatment. Absorption rate constant(K$_a$ and maximum plasma concentration(C$_{max}$) were significantly(p<0.05) reduced, and time to reach maximum plasma concentration(T$_{max}$) of griseofulvin was significantly(p<0.05) increased by phenobarbital pretreatment. Changed pharmacokinetics of griseofulvin seemed not to be due to induced enzyme activity by phenobarbital but to reduced GI absorption of griseofulvin.

• Archives of Pharmacal Research
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• v.9 no.1
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• pp.49-54
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• 1986

Effect of sodium taurodeoxycholate (TDC) infused intravenously on the pharmacokinetics of methylene blue (MB) was studied in the rat to investigate the role of ion-pair complexation in the body on drug elimination and disposition. Distribution volume (Vd) of MB was increased significantly (p< 0.05) by TDC infusion. Considering together with the fact that apparent partition coefficient (APC) of MB between phosphate buffer (pH 7.4) and n-octanol was increased markedly by TDC, the increase in Vd seemed to be the result of decreased polarity of MB by ion-pair formation with TDC. But total body clearance (CLt) and biliary excretion clearance (CLbil) of MB were not increased significantly by TDC.

• YAKHAK HOEJI
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• v.56 no.3
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• pp.158-163
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• 2012

Lidocaine has been studied for many chronic pain conditions, including postherpetic neuralgia (PHN) and recently it has also been increasingly used in transdermal drug delivery systems. In this study, pharmacokinetics of a lidocaine patch was studied in four hairless male rats. The plasma concentration was determined by a validated LC/MS/MS method after applying a $3{\times}2cm^2$ (30mg) patch for 12 hours. From the plasma lidocaine concentration vs time curves, $AUC_{0-20h}$, Cmax, and Tmax of lidocaine patch were $2,926.32{\pm}335.28ng{\cdot}h/ml$, $256.86{\pm}29.63ng/ml$, and $6.00{\pm}2.31h$, respectively.

• Korean Journal of Clinical Pharmacy
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• v.15 no.2
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• pp.100-104
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• 2005

건강한지원자에서 세프라딘 250 mg 캡슐을 오전 09:00시와 오후22:00시에 경구투여하여 세프라딘의 약물동태학적 주기변화 (생체리듬)를 검토하였다. 혈장중 세프라딘의 농도는 두 투여시간에서 유의성 있는 차이를 보여주었다. 혈장농도곡선하면적 (AUC)은 오후 때 보다 오전 투여시에 유의성 있게 증가되었으며, 생물학적반감기$(t_{1/2})$는 오후 때 보다 오전 투여시에 더 연장되었다. 전신청소를 $(CL_t)$은 오후 때 보다 오전 투여시 유의성 있게 감소되었다.

• Korean Journal of Clinical Pharmacy
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• v.27 no.2
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• pp.63-68
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• 2017

Neonates have large inter-individual variability in pharmacokinetic parameters of many drugs due to developmental differences. The aim of this study was to investigate the factors affecting the pharmacokinetic parameters of drugs, which are commonly used in critically ill neonates. Factors that reflect physiologic maturation such as gestational age, postnatal age, postconceptional age, birth weight, and current body weight were correlated with pharmacokinetic parameters in neonates, especially preterm infants. Comorbidity characteristics affecting pharmacokinetics in critically ill neonates were perinatal asphyxia, hypoxic ischemic encephalopathy, patent ductus arteriosus (PDA), and renal dysfunction. Administration of indomethacin or ibuprofen in neonates with PDA was associated with the reduced clearance of renally excreted drugs such as vancomycin and amikacin. Therapeutic hypothermia and extracoporeal membrane oxygenation were influencing factors on pharmacokinetic parameters in critically ill neonates. Dosing adjustment and careful monitoring according to the factors affecting pharmacokinetic variability is required for safe and effective pharmacotherapy in neonatal intensive care unit.

• Journal of Pharmaceutical Investigation
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• v.15 no.3
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• pp.113-120
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• 1985

The pharmacokinetics of lithium carbonate were investigated in rabbits with folate-induced renal failure. The blood level, the area under the blood concentration curve (AUC) and the biological half·life were increased significantly, and the urinary excretion was decreased significantly compared with those of normal rabbits. Correlation of serum creatinine concentration and AUC, biological half-life, and correlation of creatinine clearance and renal clearance of lithium carbonate have linear relationship respectively. In short, dosage regimen of lithium carbonate is considered to be adjusted in the dose size and the dosing interval by degree of experimental renal failure.

• Journal of Pharmaceutical Investigation
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• v.40 no.5
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• pp.297-304
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• 2010

The present work focuses on preparation of olanzapine, orally dispersing tablets by direct compression method. Effect of super disintegrant crospovidone, disintegration time, drug content on in vitro release has been studied. A factorial design was employed in formulating a prompt dispersible tablet. The selected independent variables crospovidone and fmelt showed significant effect on dependent variables i.e. disintegration time and percent drug dissolved. Disintegration time and percent drug dissolved decreased with increase in the level of crospovidone. The similarity factor $f_2$ was found to be 97.48 for the developed formulation indicating the release was similar to that of the marketed formulation. Pharmacokinetics of olanzapine after single-dose oral administration of orally disintegrating tablet in normal volunteers were evaluated and the results showed that PK parameters (Cmax, Tmax, AUC) of the designed ODT matrix were similar to those of commercial product, Zyprexa Zydis$^{(R)}$ as a reference.

• 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.25 no.3
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• pp.265-270
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• 1995

The pharmacokinetics of norfloxacin (100 mg/kg, oral) in renal failure rabbits was studied. Renal failure rabbits were induced by the i.v. injection of folate (50,100 and 150 mg/kg). These produced significant increases of serum creatinine concentration $(S_{cr})$ and blood urea nitrogen (BUN). Plasma concentration and AUC of norfloxacin significantly increased. Elimination rate constant $(K_{el})$ of norfloxacin significantly decreased, and half-life $(t_{1/2})$ of norfloxacin significantly increased. Correlation between serum creatinine concentration $(S_{cr})$ and half-life $(t_{1/2})$ of norfloxacin, and correlation between BUN and AUC of norfloxacin have linear relationship respectively. These results suggest that adjustment or the dosage regimen of norfloxacin is desirable, and serum creatinine concentration $(S_{cr})$ as well as BUN can be used an index for adjusting the dosage regimen of norfloxacin in renal failure.