Plasma concentration-vs-time curve

The pulmonary delivery of rhG-CSF (18.8 kDa) and two PEG conjugates of rhG-CSF (PI, 81.5 kDa and P2, 146.8 kDa) was investigated in rats (Niven et al. 1994). Comparison of white blood cell responses after IT instillation of 500 pg/kg PI and P2 and rhG-CSF alone, demonstrated a greater response for more substituted PEG-rhG-CSF than rhG-CSF alone. The plasma concentration vs. time curve showed... 

The bioavailability of a drug by various routes may also be determined by comparing the area under the curve (AUC) obtained from the plasma concentration vs. time curve after intravenous and other routes of administration 9... 

FIGURE 4.3 Hypothetical plasma concentration-vs.-time curve after a single oral drug dose. Calculation of the area under the plasma level-vs.-time curve (AUC) requires extrapolation of the elimination-phase curve beyond the last measurable plasma concentration, as shown by the dotted line. 

Distributed pharmacokinetics is characterized not only by spatially dependent concentration profiles but also by dose-response relationships that become spatially dependent. For example, biological responses such as cell kill are often quantified as functions of area under the concentration-vs.-time curve (ALIC). In compartment models, response is frequently correlated with the area under the plasma-concentration-vs.-time curve, where... 

PK = pharmacokinetic Cl = clearance AUC = area under the plasma concentration vs. time curve ERBT = erythromycin breath test IM = intramuscular IV = intravenous... 

AUC area under the plasma concentration vs time curve, autoantibodies antibodies directed against self tissues or constituents, autoimmune immune response in which antibodies are directed against the organism itself, autoradiography use of radiolabelled compounds to show distribution in a tissue, organ or even whole animal. 

The pharmacokinetics of pyridostigmine in healthy human volunteers, myasthenic patients, and in animal species such as dogs and rats are enumerated in Table 5.1. The numerical data on pharmacokinetic parameters, such as t j bioavailability (F), area under the plasma concentration vs. time curve (AUC), volume of distribution (Vd), and clearance (Cl) after i.v. and oral administration to humans and animals, are summarized in this table. 

In this work SC-27166 (Va) was administered orally and d4-SC-27166 (Vb) intravenously to two baboons. Dg-SC-27166 (Vc) was used as the internal standard to quantify the concentration of Va and Vb in plasma and urine. Comparison of the area under the plasma concentration vs time curve showed that oral bioavailability was approximately 76%. 

In a single healthy volunteer, the chiral skeletal muscle relaxant methocarbamol was found to possess stereoselectivity in plasma concentrations after intravenous administration. Based on the plasma concentration vs. time curve, the S enantiomer appeared to be cleared more rapidly than antipode, although pharmacokinetic data were not reported [215]. 

Fig. 6. Simulated plasma drug concentration vs. time curves after intravenous administration (a) showing the j-axis in numeric scale, and (b) showing the curve when the v-axis is converted to logarithmic scale.

Fig. 13. Plasma drug concentration vs. time curve after administrations of multiple oral doses at 8-hour intervals.

Figure 5.2 Plasma concentration curve of drug after single and repeated administration Csj. nax, maximal steady-state plasma concentration after repeated administration Css av, average steady-state concentration after repeated administration Css mm- minimal steady-state concentration after repeated administration n. maximal plasma concentration after single oral dose t Inax. time to maximal concentration after single oral dose t plasma half-life after single oral dose AUC, area under the concentration vs. time curve...

PKpharmacokinetics, maximum plasma concentration, CL systemic clearance, AUC area under the concentration vs. time curve, SNP single-nucleotide polymorphism... 

The elimination half-life of the "second component" discussed previously was 1.9 h and the mean area under the concentration vs time curve (AUC) was 8.2 mg/L h after a single oral dose of 320 mg (De Bemardi Di Valserra et al., 1994). The AUC of the "second component" produced by a 640-mg rectal dose of saw palmetto extract was 10 mg/L x h, and plasma levels were detectable up to 8 h post-dose (De Bernardi Di Valserra and Tripodi, 1994). 

Figure 10.2 Pharmacokinetics of intravenous T-20 administration. The graphs show the expected changes in plasma concentration vs time after intravenous administration of a single injection (dashed line) or multiple injections (solid line) of intravenous T-20 (lOOmg/dose). The curves are based on the half-life (1.8 h) and volume of distribution (4.7 L) measured in 17 human volunteers [4] using a one-compartment model (see Equation 7-3). Because of its rapid elimination, multiple doses are needed to maintain the peptide level in the effective range.

Fig. 1.4.4 Drug concentration in plasma vs time curve of drug administered orally.

Figure 1.9 Plasma concentration-time (Cp vs T) curve following oral administration of equal doses, D, of a drug every 4 hours...

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