• 대한화학회지
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• 제55권1호
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• pp.46-49
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• 2011

감도가 높고 선택적인 추출-분광광도법은 미량의 시메티딘의 측정을 위해 개발되어 왔다. 이 방법은 클로로포름안에 브로모티몰 블루(BTB)와 함께 이온 쌍으로 시메티딘의 추출에 기초했다. 그리고 417 nm에서 흡광도를 측정하고 있다. pH, BTB의 농도, 클로로포름의 부피, 섞는 시간과 같은 다른 변수들의 효과를 연구하였다. 또한, 추출에서 간섭이온의 효과도 연구하였다. 보정곡선은 0.9997의 상관계수와 함께 0.25~8 ug/mL의 범위에서 선형이다. 3Sb에 기초한 검출한계는 0.14 ug/mL이고 시메티딘의 0.1과 4.0 ug/mL의 10번 측정에 대한 상대표준편차는 3.2와 1.49%이었다. 제안된 방법은 좋은 회수와 함께 약제 샘플에서 시메티딘의 측정에 적용되었다.

• Journal of Pharmaceutical Investigation
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• 제23권2호
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• pp.81-87
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• 1993

Five crystalline forms of cimetidine, four anhydrous and a monohydrate, have been prepared, and their thermal behavriours have been studied by differential thermal analysis and thermo-gravimetry. The dissolution rates of the five forms were determined in distilled water at $37^{\circ}C$. The results showed a significant difference in the dissolution rate. Polymorphic transformation occurred spontaneously during storage at room condition and was accelerated by applied energy during formulation process-milling.

• 분석과학
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• 제23권5호
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• pp.457-464
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• 2010

먹는물(정수) 중에 잔류하는 버지니아마이신을 비롯한 macrolide 계열 의약물질 3종과 시메티딘을 동시에 정량 및 정성 분석하는 방법을 확립하였다. HLB 카트리지를 사용하여 분석물질을 추출/정제 및 농축한 후, HPLC/ESI-MS/MS를 이용하여 4종의 물질들을 효과적으로 분리하고 감도 좋게 검출할 수 있었다. 정량분석을 위해서 0.01~2.0 ng/mL 범위에서 $r^2$=0.995이상의 높은 직선성을 나타내는 검량선을 얻었으며, 시메티딘(37.7~48.1%)을 제외한 macrolide 계열 3종 의약물질은 64.7~118.1% 범위의 양호한 회수율을 나타내었다. 바탕 정수에 소량 첨가하여 얻은 분석방법의 검출한계와 정량한계는 각각 1.6~74.8 pg/mL 와 5.5~249.7 pg/mL 범위의 높은 감도를 나타내었다.

• 한국임상약학회지
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• 제3권2호
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• pp.163-168
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• 1993

The influence of cimetidine pretreatment(100mg/kg, single i.p.) on the hepatic blood flow was investigated using pharmacokinetic parameters of indocyanine green(ICG) in the rat on the basis of hepacc perfusion-limited model. ICG(1mg/kg) was respectively administered via femoral and portal vein to the control and to the cimetidine-pretreated rats. The rate constant K12, K20 and the systemic clearance(CLt) of ICG were significantly(p<0.05) decreased ill the cimetidine-pretrea-to(B rats, but no significant diffirences were observed in hematocrit and liver weight. The biliary excretion rates of ICG were also decreased regardless of the route of administration in the cimetidine-pretreated rats. And also the hepatic blood flow in rats was decreased about $16\%$ by cimetidine. It may be concluded that the decreased hepatic blood flow with cimetidine mainly contributed to the decreased hepatic uptake and the decreased systemic clearance of ICG.

• 약학회지
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• 제29권6호
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• pp.362-366
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• 1985

These paper was attempted to investigate the mechanism of increased blood level of sulfisomidine by cimetidine pretreatment pharmacokinetically. Especially, effect of cimetidine pretreatment on both renal clearance and biliary clearance of sulfisomidine was studied in rabbits. The results are as follows. The blood level of sulfisomidine administered intravenously in dose of 25mg/kg was elevated significantly by cimetidine pretreatment. Relative bioavailability and biological half-life were increased significantly by cimetidine pretreatment. Overall elimination rate constant ($betha$) and distribution rate constant ($K_{13}$) of sulfisomidine were decreased significantly by cimetidine pretreatment. The renal and biliary clearance of sulfisomidine were decreased significantly compared with those of control rabbits by cimetidine pretreatment. The results may be also related to the inhibition of sulfisomidine metabolism enzyme activity or reduction of blood flow in the liver.

• 한국임상약학회지
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• 제3권1호
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• pp.1-13
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• 1993

The intraction between cimetidine and rifampicin was studied pharmacokinetically in normal human subjects. The serum level and the area under the serum concentration curve(AUC) of rifampicin administrated orally were elevated significantly by cimetidine. Volume of distribution, total clearance and elimination rate constant of rifampicin were reduced significanyly by cimetidine. Biological half-life of rifampicin was prolonged significantly by cimetidine. The mechanism of this results is probably related to the inhibition of rifampicin metabolism(deacetyl form) or reduction of blood flow in the liver. It is desirable that dosage regimen of rifampicin shoud be adjusted when combined with cimetidine in clinical pharmacy practice.

• 한국임상약학회지
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• 제10권1호
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• pp.19-24
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• 2000

The effect of cimetidine on the pbarmacokinetic parameters of cyclosporine (intravenous administration) were determined in 6 healthy volunteers (22-48 years old, 48-62 kg) by cross-over design. Cyclosporine and cyclosporine metabolites in whole blood were analysed by fluororescence polarization immunoassay (TDx-FLX). The blood concentrations of cyclosporine After pretreatment with cimetidine (200 mg bid, for 3days) were increased significantly at 8-12 hrs compared to the control (p<0.05). The ratios of blood concentrations of cyclosporine metabolites (M1, M17) to parent drug were decreased significantly at 8-12 hrs (p<0.05). Total body clearance (CL) was also decreased significantly (p<0.05), and area under the curve $(AUC,\%)$ was increased but not significant.

• 약학회지
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• 제32권5호
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• pp.319-327
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• 1988

Pharmacokinetic interaction of cimetidine and isoniazid was investigated in the rabbits. Isoniazid was administered orally at a dose of 30mg/kg to six rabbits after 10, 20, and 30mg/kg pretreatment of cimetidine twice a day for 10days. Concentration of the free and the total isoniazid in the blood and the urine was determined by spectrophotometer. Relative bioavailability and biological half-life($t\frac{1}{2}{\beta}$) were increased significantly by cimetidine pretreatment. Overall elimination rate constant and total clearance of isoniazid were decreased significantly by cimetidine pretreatment. The ratio of metabolites to isoniazid in the blood and the urine was decreased significantly by cimetidine pretreatment. Relative bioavailability, INAH to metabolites ratio in the blood and decrease in total clearance were highly correlated with the does of cimetidine pretreated. This result might be due to the inhibition of isoniazid metabolism in the liver by cimetidine pretreatment.

• Journal of Pharmaceutical Investigation
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• 제21권4호
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• pp.247-251
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• 1991

Effects of aluminum magnesium hydroxide (A) and cimetidine (C) on the pharmacokinetics of minocycline (M) were investigated in female rats. Blood samples were collected at various time intervals until 36 hrs following oral dosing of drugs. Plasma minocycline concentrations were determined by HPLC. Control group (M), $T_1$ group (M+A), $T_2$ group (A+M after 2 hrs), $T_3$ group (M+A after 2 hrs), $T_4$ group (M+C) and $T_5$ group (C+M after 2 hrs) were divided to examine interaction of the drugs with minocycline. Plasma minocyline level-time curves were well described by two-compartment open model with first-order absorption in rats. Antacid treatment was associated with reduced of 71.0, 45.9, 35.7% in minocycline absorption rate $constant(K_{\alpha})$, maximum plasma $concentration(C_{max})$, and relative $bioavailability(F_{rel})$, respectively. Cimetidine treatment group exhibited no significant changes in plasma level-time curve when compared with control group and did not affect minocycline absorption as by any of these three parameters.

• 약학회지
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• 제48권5호
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• pp.297-302
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• 2004

The purpose of the present study was to evaluate the bioequivalence of two cimetidine tablets, Tagamet (Yuhan Pharm. Co., Ltd.) and Nex (Bi-nex Pharm. Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The cimetidine release from the two cimetidine tablets in vitro was tested using KP Apparatus I method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solutions and water). The dissolution profiles of two cimetidine tablets were very similar at all dissolution media. Twenty four healthy male volunteers were divided into two groups with a randomized $2{\times}2$ cross-over study. After four tablets (800 mg cimetidine) were orally administrated, blood was taken and the concentrations of cimetidine in serum were determined using HPLC with UV detector. The pharmacokinetic parameters such as $AUC_{t}$, $C_{max}$ and $T_{max}$ were determined. The result showed that the differences in $AUC_{t}$, and $C_{max}$ between two cimetidine tablets based on the Tagamet were -6.82% and -12.98%, respectively. There were no sequence effects between two tablets in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) (e.g., log(0.90)log(0.97) and log(0.82)log(0.93) for $AUC_{t}$ and $C_{max}$, respectively), indicating that Thrumetin tablet was bioequivalent to Tagamet tablet.