Question

Which of the following statement is correct for describing characteristic feature of non-linear pharmacokinetics?

• A. \( \text{Area under the curve is proportional to the dose.} \)
• B. \( \text{Elimination half-life remains constant.} \)
• C. \( \text{Area under the curve is not proportional to the dose.} \)
• D. \( \text{Amount of drug excreted remains constant.} \)

Hint:

Think of "non-linear" as "not following the rules." In linear pharmacokinetics, everything scales with the dose. In non-linear, it doesn't.

Answer 1

The Correct Option is C

Non-linear pharmacokinetics occurs when the pharmacokinetic parameters of a drug (such as absorption, distribution, metabolism, and excretion) change with the dose or concentration of the drug. This is often due to the saturation of processes involved in these phases, such as saturable metabolism or protein binding. In non-linear pharmacokinetics: - The area under the curve (AUC) of a concentration-time profile is not directly proportional to the dose because the clearance can change with concentration. - The elimination half-life may not remain constant as it can be dose-dependent due to saturation of elimination pathways. - The amount of drug excreted may not increase linearly with dose due to saturation of transporters or metabolic enzymes. Therefore, the correct statement describing a characteristic feature of non-linear pharmacokinetics is that the area under the curve is not proportional to the dose.