The Half-Life
The Half-Life
Drug half-life is calculated from a plasma concentration (Cp) versus time curve.
Inject IV dose and observe.
Note the curve shape after IV injection - this "first-order" elimination curve applies to most drugs.
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The Half-Life
The half-life (t1/2) is the time taken for the concentration to halve. Repeat using a log graph.
Observe how the half-life is the same at all concentrations.