• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.11a
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• pp.93-106
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• 1997

약물 투여 후 약효의 출현은 흡수, 분포 등의 약동학적 단계(pharmacokinetic phase)를 거쳐 수용체 부위에서 약물과 수용체 사이의 약력학적(pharmacodynamic) 상호작용에 의해 나타난다. 따라서 약물요법 시 약효나 독성 발현의 큰 개인차는 약동학적 또는 약력학적 개인차에 의해 나타나며, 많은 약물에서 약효의 개인차는 흔히 약동학적 차이가 주역할을 함이 알려져 있고, 약물의 특성에 따라 약물의 대사 및 배설과 관련 있는 신장, 간장 및 심장 질환자에서는 현저한 약동학적 변화로 용법 조정이 필수적으로 요구되는 경우가 많다. 약동학적 개인차는 안전역이 좁은 약물에서 더욱 문제가 되며 이러한 약물의 적정 요법을 위해서는 수용체 부위와 평형을 이루고 있는 혈장약물농도를 적정 유지하는 것이 약동학적 개체차를 배제할 수 있는 한 방안이다. 근자에 이르러 체액내 약물 및 이의 대사물을 측정하는 분석 화학의 발전과, 임상 약물 동태학(clinical pharmacokinetics)의 도입 등으로 개개 환자에서의 적정 약물요법을 위한 TDM (Therapeutic Drug Monitoring)이 구미에서는 이미 보편화되어 있다 또한 국내에서도 이러한 새로운 의료분야의 연구 및 임상응용의 필요성이 점차 증가하고 있으므로, 이러한 시대적 요구에 발맞추어 본 지면을 통하여 임상약리학적 지식을 이용한 혈장 농도 데이터의 분석을 통하여 개개인에서의 적정 약물요법을 제시하는 TDM에 관하여 소개하고자 한다.

• CELLMED
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• v.4 no.3
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• pp.17.1-17.8
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• 2014

Herbal remedies are commonly used by patients worldwide. Because these herbal preparations share the same metabolic and transport proteins with prescribed medicines, the potential for a drug-herb interaction is substantial and is an issue of significant concern. This review paper summarizes drug-herb interactions involving inhibition or induction of cytochrome P450 enzymes, drug transporters as well as modulation of drug pharmacodynamics. An increasing number of in vitro and animal studies, case reports and clinical trials evaluating such interactions have been reported, and implications of these studies are discussed in this review. The most commonly implicated drugs in the interaction include anticoagulants, antiplatelets, immunosuppressants, anti-neoplastics, protease inhibitors, and some antidepressants. Pharmacokinetic and/or pharmacodynamic interactions of five commonly used herbal remedies (danshen, garlic, Ginkgo biloba, ginseng, and St John's wort) with these drugs are presented, with focus of discussion being the potentials for interaction, their mechanisms and clinical implications. There is a necessity for adequate pharmacovigilance to be carried out in minimizing unanticipated but often preventable drug-herb interactions.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.214-217
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• 2002

Cyclosporin A (CSA) is a poorly water-soluble cyclic peptide comprising 11 amino acids. It inhibits T-lymphocyte function that plays an important role in the induction of immune response. The potent immunosuppressive activity of CSA has been used for the prevention of rejection following transplantation of liver, kidney and bone marrow, etc. The use of CSA has been often limited by several disadvantages including low bioavailability, narrow therapeutic window, nephrotoxicity, hepatotoxicity and neurotoxicity. Moreover, CSA injection is limited to patients who are unable to take the oral preparations, because it has a risk of anaphylactic shock and nephrotoxicity due to Cremophor EL$\textregistered$, a solubilizing agent used in the commercial intravenous formulation. Owing to above mentioned disadvantages of commercial products, there is a great interest in the development of the alternative dosage forms. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.212-213
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• 2002

Using the isolated perfused rat heart this study investigated 1) the cardiac uptake of idarubicin (IDA), 2) the role of P-glycoprotein (P-gp) in the uptake process, 3) the formation of IDOL from IDA in the heart, and 4) the effect of P-gp inhibitors (verapamil, amiodarone, PSC 833), doxorubicin, hypothermia, xanthine derivatives (caffeine, theophylline) and metabolism inhibitors (rutin, phenobarbital) on the pharmacokinetics and pharmacodynamics of IDA using a mathematical modeling approach. A minimal model was constructed; the differential equations were numerically solved and fitted to the data using the ADAPT II-software package using maximum likelihood estimation assuming that the measurement error has a standard deviation which is a linear function of the measured quantity［1］. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.417.2-418
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• 2002

The rhGH-loaded PLGA microsphere formulation was prepared using a double emulsion process from hydrophilic 0:50 poly(D.L-lactide-co-glycolide) (PLGA) polymers. To investigate the sustained efficacy of this formulation, ts pharmacodynamic characteristics were analyzed. It showed particle size of ca 53.1 $\mu\textrm{m}$ with high drug ncorporation efficiency and it was sucutaneously administrated to hypophysectomized rats and whole body rowth responses of this formulation were compared to those of the different dosing patterns of rhGH. (omitted)

• East Asian mathematical journal
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• v.36 no.1
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• pp.81-90
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• 2020

Many compartment models assume a kinetically homogeneous amount of materials that have well-stirred compartments. However, based on observations from such processes, they have been heuristically fitted by exponential or gamma distributions even though biological media are inhomogeneous in real environments. Fractional differential equations using a specific kernel in Pharmacokinetic/Pharmacodynamic (PKPD) model are recently introduced to account for abnormal drug disposition. We discuss a tumor growth inhibition (TGI) model using fractional-order derivative from it. This represents a tumor growth delay by cytotoxic agents and additionally show variations in the equilibrium points by the change of fractional order. The result indicates that the equilibrium depends on the tumor size as well as a change of the fractional order. We find that the smaller the fractional order, the smaller the equilibrium value. However, a difference of them is the number of concavities and this indicates that TGI over time profile for fitting or prediction should be determined properly either fractional order or tumor sizes according to the number of concavities shown in experimental data.

• Sleep Medicine and Psychophysiology
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• v.19 no.1
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• pp.18-21
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• 2012

Parasomnias induced by hypnosedatives are rare but serious side effect. Such parasomnias have not been reported with all hypnosedatives. However, frequent use of hypnosedatives, particularly nonbenzodiazepine receptor agonists is associated with parasomnias. Associated symptoms are sleep eating, sleepwalking with object manipulation, sleep conversations, sleep driving, sleep sex and sleep shopping etc. Mechanisms include high affinity for $GABA_A$ receptor, interruption of the consolidation phase of memory formation by drug, pharmacokinetic or pharmacodynamic drug-drug interaction and concomitant administration with alcohol. Managements for parasomnias induced by hypnosedatives involve stopping medication, switch to other medications or nonpharmacological treatment, lowest effective dose of NBRAs (Non-Benzodiazepine Receptor Agonists), taking into consideration drug-drug interactions, identification and treatment of underlying disease states.

• Neonatal Medicine
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• v.15 no.2
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• pp.113-118
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• 2008

Clinical trials in neonates of different gestational age, birth weight, postnatal age and general health status are needed to assure safe and optimal evidence-based-therapy to this special population. Pharmacodynamic maturation must be considered in grouping the neonates for clinical trials. Informed consent from the parents, protection of the neonates participating in the clinical trials, adherence to good clinical practice guidelines, and designation of short term and long term outcomes must be taken into consideration from the beginning of the trials. Collaboration between centers will be helpful in overcoming the problem with small patient size. Many of these challenges are surmountable and an well-designed clinical trial will improve the mortality and morbidity in these very small children.

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.1
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• pp.11-16
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• 2005

Chemical mixtures of components, each of which are present at less than guidance concentrations, may be hazardous due to additivity, interactions, or both. Toxicological interactions may increase the health hazard above what would be expected from an assessment of each component singly, or all components additively. So chemical mixture are a particular issue in public health. There are several approach to assess whether there are additivity or interaction in assessing toxicological effects, such as, components-based approach, physiologically-based pharmacokinetic /pharmacodynamic(PBPK/PD) models, hazard index method, and weight-of evidence method. If we consider interaction or additivity effects in assessing the health effects of chemcial mixtures, we can get more accurate information about toxicological effects and dose-response relationship in chemical mixtures.

• 대한임상약리학회:학술대회논문집
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• 1998.12a
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• pp.52-52
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• 1998