No abstract available.

No abstract available.

The third equation on page 44 should be corrected.

The equations on page 162 should be corrected.

In the published version of this article, the contents of Table 1 (‘Demographic characteristics of subjects’) are incorrect.

This tutorial deals with basic concepts of clearance, the most important parameter in pharmacokinetics but often challenging for students in clinical pharmacology. Its relationships with dose, concentration and elimination rate are discussed using a physical model and examples of commonly used drugs, as well as its physiological aspects pertaining to the blood flow to differing organs. Finally, application of clearance to the calculation of maintenance dose rate and half-life is used to show how it is essential in pharmacotherapy and clinical pharmacology.
Drug Therapy ; Half-Life ; Humans ; Pharmacokinetics ; Pharmacology, Clinical

No abstract available.
Chromosome Aberrations*

To address the debate on the safety of generic substitution quantitatively, the author compared the change in AUC in virtual patients who were simulated for several different scenarios of generic substitution. In four scenarios of original (branded) to generic and generic to generic substitution, 5,000 virtual patients were simulated per scenario using the programming software R. The mean population AUC of generics ranged from 90-110% (scenarios A and B) and 80-123.5% (scenarios C and D) of the AUC of the original. Those patients who had an AUC change (ratio) as a result of drug substitution of less than 0.67 or greater than 1.5 were considered to be in potential danger due to the substitution. We found that less than 6% of patients fell outside of the cutoff range of 0.67-1.5 as a result of original to generic substitution. However, in the case of generic to generic substitution, the proportion was as high as 9-12%. This alerts us to the potential danger of generic substitution, especially for drugs with narrow therapeutic indices.
*Area Under Curve ; Attitude to Health ; Computer Simulation ; Drug Prescriptions ; Drugs, Generic/*pharmacokinetics/therapeutic use ; Humans ; Patients/psychology/statistics & numerical data ; Software ; Therapeutic Equivalency

More than 60 antiviral agents for various infectious diseases such as herpes, hepatitis, influenza, and AIDS are currently prescribed worldwide. Among the viral infections, hepatitis B and influenza are those frequently seen in primary care situations in Korea. This review discusses the anti-hepatitis B (HBV) drugs entecavir and adefovir, and the anti-influenza drugs oseltamivir and zanamivir. In addition, the pharmacology and therapeutic guidance suggested by the Korean Association for the Study of the Liver were reviewed for entecavir and adepovir, the most frequently prescribed anti-HBV drugs. For influenza, oseltamivir is commonly used despite debates on neuropsychiatric safety issues and zanamivir may be used when an inhalation form is necessary. Although currently used drugs show considerable clinical efficacy, efforts to optimize their use and further research to find new molecules that may overcome their limitations are necessary.
Adenine ; Antiviral Agents ; Communicable Diseases ; Guanine ; Hepatitis ; Hepatitis B ; Influenza, Human ; Inhalation ; Korea ; Liver ; Organophosphonates ; Oseltamivir ; Primary Health Care ; Zanamivir

The number of clinical trials sponsored by global pharmaceutical companies performed in countries other than the U.S. and Western Europe has been steadily increasing over the past decade. Among those emerging countries, Korea deserves attention for its rapid growth in the number of trials and sites. As of 2009, Korea was ranked the tenth country in the number of clinical trials registered at http://clinicaltrials.gov. This is remarkable growth given that it was not included in the top 30 countries in 2005. High population density, qualified medical professionals, regulatory changes including Investigational New Drug-New Drug Application (IND/NDA) separation, acceptance of International Conferences on Harmonization-Good Clinical Practices (ICH-GCP) by Korea Food&Drug Administration (KFDA), and governmental policies to boost clinical trials were the most influential factors that caused such an outstanding achievement. The Korean National Enterprise for Clinical Trials (KoNECT), an organization founded to lead initiatives to improve the milieu for clinical trials, has been playing a pivotal role in the steering of 15 regional clinical centers designated by the government. Based upon improvements in infrastructure so far, diversity in therapeutic areas and the proportion of early phase trials are expected to grow. Korea has grown to be one of the major countries in the clinical trial market, which was made possible by the cooperation of industry, academia and government. Further investment and efforts to solve current challenges will allow such growth to continue into the next decade.
Achievement ; Congresses as Topic ; Europe ; Investments ; Korea ; Population Density