Plasma conc-time profile

Examine the plasma conc-time profiles after administration of different doses.

Similar rate of decline
Similar slope at 10 mg/L

The initial drug plasma conc is :

Cp0 =

Dose

Vd

The initial drug conc will be different after administration of different doses. This means that the plasma conc-time profiles will be different after administration of different doses since the rate of drug metabolism is dependent on the drug conc.

-dA

dt
=

Vmax Cp

Km + Cp

Notice that at any given drug conc, the rate of drug elimination (the slope of the curve) is similar regardless of the dose of the drug.