Spring Intro 2023

Mike Kelly

Basic Principles: Pharmacokinetics - Absorption

 For oral administration, it is the process by which a drug moves from the site of administration across the gut membrane and ultimately into the systemic circulation

Rate of absorption measured by Ka and tmax

tmax

Ka (h -1 ) – absorption rate constant

tmax (h) – time taken to reach the maximum plasma concentrations (Cmax) Tmax important when considering onset of action

Drug concentration

Time after dose

Time

7

7

Basic Principles: Pharmacokinetics - Absorption

Extent of absorption measured by Cmax and AUC

Cmax (ng/ml) – maximum plasma concentration

Cmax

AUC (ng.h/ml) – area under the plasma concentration time curve

Cmax important to when considering efficacy and/or adverse events

Drug concentration

AUC

Rate of absorption and Cmax are related

Time after dose

8

8

4