True about t 1/2 ?: (A) Time required to reduce the plasma conc. to half, (B) Zero order kinetics - t 1/2 remains constant, (C) First order kinetics - t 1/2 increases, (D) Complete drug elimination occurs in 2-3 t 1/2
Answer is A. Ans. is 'a' i.e., Time required to reduce the plasma conc. to half Half life PA It is the time required to reduce the plasma concentration to half (50%) of the original value. It determines the dosing interval and time required to reach the steady state. It is a secondary pharmakokinetic parameter derived from two primary parameters, volume of distribution (Vd) and clearance (CL).