Distribution, pharmacokinetics

Pharmacokinetics Distributed in extracellular fluid and does not appear in red blood cells. No metabolism occurs. Rapidly excreted in the urine. Half-life 1.4-3 hr. 

Pharmacokinetics Distributed mainly in blood and to some extent in extravascular fluid. Iron sucrose is dissociated into iron and sucrose by the reticuloendothelial system. The sucrose component is eliminated mainlyby urinary excretion. Haif-life 6 hr. 

Pharmacokinetics Distributed primarily in extracellular fluid. Primarily eliminated by the kidneys. Half-life 1.3 hr (increased in impaired renal function). 

The standardization is the prerequisite for a constant pharmacological answer. This chapter will discuss the recent investigations we have performed on the standardized P. ginseng extract G115 (GINSANA ), its standardization, the pharmacological models we have used to establish its activity, and the pharmacokinetic distribution and metabolism of the ginsenosides. 

Metabolic studies identify and quantify the residues. These studies should simulate the conditions of use of the drug in animal husbandry as closely as practicable. The pharmacokinetics (distribution and elimination) of the residues should be examined between the time of administration of the drug and the time the animals enter the human food supply. 

In addition to the possibility of improving therapeutic effects, structural modifications utilizing pharmacokinetic analysis of drug distribution can explain and potentially avoid toxlcitles by selective distribution away from specific tissues. This has been demonstrated in relation to aminoglycoside nephrotoxicity, 5 and accumulation of -adreno-ceptor antagonists in the lungs.However, the full potential for the use of pharmacokinetic distribution volumes in drug development has yet to be realized. 

Willhite CC, Ferm VH, Zeise L. 1990. Route-dependent pharmacokinetics, distribution, and placental permeability of organic and inorganic selenium in hamsters. Teratology 42(4) 359-371. 

The selection of these drugs for monotherapy or in the stepped-care approach is based on several factors, including their similar mechanism of action, preexisting conditions, pharmacokinetics, distribution, and metabolism. The Q2-adrenergic antagonists show a similarity in adverse effects. 

PHARMACOKINETICS, DISTRIBUTION, BIO AVAILABILITY, AND RELATIONSHIP TO ANTIBIOTIC RESIDUES... 

Papich and Riviere report marked variability in aminoglycoside pharmacokinetics (distribution, clearance, and half-life) with altered physiologic or pathologic states, including pregnancy, obesity, dehydration, immaturity, sepsis, endotoxemia, and renal disease. The latter influence is predictable from the fact that body clearance is dependent almost entirely on renal excretion. Martin-Jimenez and Riviere concluded that aminoglycoside pharmacokinetics can be predicted across species by population pharmacokinetic modeling. ... 

Numerous transporter knockout animals are available to evaluate pharmacokinetic distribution of NCEs. Schinkel et al. (1994) generated the knockout mdrla (P-gp) mouse model that became 100-fold more sensitive to the neurotoxic pesticide ivermectin. This classic model has demonstrated how critical P-gp is to preventing xenobiotics from crossing the BBB (Loscher and Potschka, 2005 Kusuhara and Sugiyama, 2005 Terasaki and Ohtsuki, 2005 ... 

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