MCQ Pharmacology Answer 26

Absorption follows first order kinetics when the absorption velocity is proportional to the concentration of the drug, i.e., a constant fraction of the total amount of drug present is transported in equal units of time. So, if 50 percent of the amount present is absorbed in 12 minutes, then 50 percent of what is left will be absorbed over the next 12 minutes. Thus, a total of 75% will be absorbed in 24 minutes.

The elimination of chloramphenicol from the serum following its i.v. administration shows a steady decrease in concentration as the drug is eliminated.

Administration of this form, either by solution or by rapidly dissolving solids (i.e. pills) often obey first-order kinetics. Absorption is characterized by evaluating the absorption rate constant ka from plasma concentration versus time data graphs.

Category: Pharmacology MCQs