TIME multiples of elimination t12

FIGURE 1-4 Fundamental pharmacokinetic relationships for repeated administration of drugs. The blue line is the pattern of drug accumulation during repeated administration of a drug at intervals equal to its elimination t1/2 when drug absorption is 10 times as rapid as elimination.

As the rate of absorption increases, the concentration maxima approach 2 and the minima approach 1 during the steady state. The black line depicts the pattern during administration of equivalent dosage by continuous intravenous infusion. Curves are based on the one-compartment model. Average concentration (Css) when the steady state is attained during intermittent drug administration is

where F is fractional bioavailability of the dose and T is dosage interval (time). By substitution of infusion rate for F • dose/T, the formula is equivalent to Equation (1-2) and provides the concentration maintained at steady state during continuous intravenous infusion.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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