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"Many drugs and other xenobiotics (e.g., preservatives, insecticides, and plastifiers) contain hydrolyzable moieties such as ester or amide groups. In biological media, such foreign compounds are, therefore, important substrates for hydrolytic reactions catalyzed by hydrolases or proceeding non-enzymatically. Despite their significance, until now, no book has been dedicated to hydrolysis and hydrolases in the metabolism of drugs and other xenobiotics. This work fills a gap in the literature and reviews metabolic reactions of hydrolysis and hydarion from the point of views of enzymes, substrates, and reactions."

"The medical benefits of a drug are not only dependent on its biological effect, but also on its "life cycle" within the organism, from its absorption into the blood, distribution to tissue until its eventual breakdown or excretion by the liver and kidneys.Here, the authors, all of them employed at Pfizer in the discovery and development of new active substances, discuss the significant parameters and processes important for the absorption, distribution and retention of drug compounds in the body, plus the potential problems created by their transformation into toxic byproducts. The authors cover everything from the fundamental principles right up to the latest developments using high throughput methods to analyze the pharmacokinetic properties of active substances.Particular emphasis is placed on the impact of pharmacokinetic parameters on the discovery of new drugs, one of the most challenging tasks in global pharmaceutical research."

"Many times drugs work fine when tested outside the body, but when they are tested in the body they fail. One of the major reasons a drug fails is that it cannot be absorb by the body in a way to have the effect it was intended to have. Permeability, solubility, dissolution, and charged state of ionizable molecules :- Helps drug discovery professionals to eliminate poorly absorbable molecules early in the drug discovery process, which can save drug companies millions of dollars.- Extensive tabulations, in appendix format, of properties and structures of about 200 standard drug molecules.This book attempts to describe the state of the art in measurement of ionization constants (pKa), oil–water partition coefficients (log P/log D), solubility, and permeability (artificial phospholipid membrane barriers). Permeability is covered in considerable detail, based on a newly developed methodology known as parallel artificial membrane permeability assay (PAMPA)."

"A valuable reference tool for professionals involved in the industry, Drug Metabolism in Pharmaceuticals covers new tools such as LC-MS and LC-MS-NMR along with experimental aspects of drug metabolism. This work fills a gap in the literature by covering the concepts and applications of pharmaceutical research, development, and assessment from the point of view of drug metabolism. By providing both a solid conceptual understanding of the drug metabolism system, and a well illustrated, detailed demonstration and explanation of cutting edge tools and techniques."

"Salah satu masalah penggunaan obat yang dihadapi dokter di klinik ialah ketidakseragaman respons yang diperlihatkan penderita terhadap pemberian Obat dengan jenis dan dosis yang sama bila diberikan pada sekelompok penderita dengan jenis dan berat penyakit yang sama biasanya hanya memberikan efek terapi pada sebagian penderita saja. Penderita lainnya mungkin tidak memperlihatkan efek sama sekali atau mengalami efek toksik.Variasi respons ini bukan hanya terjadi antar individu, tetapi juga teujadi antar populasi dan antar etnik (Wood & Thou, 1991; Darmansjah & Muchtar, 1992). Dewasa ini diketahui bahwa salah sate faktor penting yang menyebabkan terjadinya fenomena tersebut di atas ialah adanya perbedaan kemampuan antar-individu dalam memetabolisme that, yang mengakibatkan terjadinya perbedaan besar pads kadar 'steady state' dalam plasma antar individu (Vesell, 1977; Vesell, 1984a; Sjngvist et al., 1987).Variasi respons obat yang besar antar-individu merupakan paduan pengaruh faktor genetik dan lingkungan (penyakit, polusi, nutrisi, dB). Menurut Vesell (1977), faktor genetik mempunyai pengaruh yang lebih besar dad faktor lingkungan. Faktor genetik ini dapat dikendalikan oleh gen tunggal (monogenik) atau banyak gen oleh gen tunggal. Bila dibuat sebaran frekuensi kecepatan metabolisme obat-obat ini dari suatu populasi, akan diperoleh cm yang khas yaitu adanya distribusi dengan dua modus (bimodal). Modus yang sate menggambarkan sebaran 'rapid acetylator' (RA) atau 'extensive metabolizer' (EM), sedangkan modus lainnya meggambarkan sebaran 'slow acetylator' (SA) aiau 'poor."