This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pharmacokinetics, Subject name: Pharmacology
Which of the following statements is true about steady state? 
Select and explain. 
A. It does not depend upon half life, B. Plasma concentration achieved is independent of dose rate, C. Longer is dosing interval, lesser is the difference between peak and trough values, D. Rate of administration is equal to rate of elimination
D: Rate of administration is equal to rate of elimination
Answer: D: Rate of administration is equal to rate of elimination 
Explanation: Steady state is achieved when rate of administration is equal to rate of elimination Three impoant points to remember: Steady state is achieved within 4-5 half lives Dosing rate (dose per unit time) determines the average plasma concentration obtained at steady state. Frequency - drug when given intermittently, concentration will vary around baseline - peak and trough are obtained Longer interval - difference between peak and trough is more Lesser the interval - difference between peak and trough is less