This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'True about t 1/2 ? \nSelect and explain. \nA. 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', 'role': 'user'}, {'content': "Answer: A \nExplanation: 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).", 'role': 'assistant'}]