This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cell Wall Synthesis Inhibitors, Subject name: Pharmacology
All of the following are true regarding penicillin G except:- 
Select and explain. 
A. Probenecid decreases it duration of action, B. It is active against gram positive organisms, C. It Splits into 6 amino penicillanic acid by amidase, D. It acts by inhibiting cell wall synthesis
A: Probenecid decreases it duration of action
Answer: A: Probenecid decreases it duration of action 
Explanation: Probenecid inhibits tubular secretion and increase the duration of action of penicillin G Penicillin G is sho acting. To overcome this problem: Benzathine and procaine group can be added to penicillin G to make it long acting. Benzathine penicillin G is longest acting penicillin. Probenecid can be administered with penicillins. Former inhibits the tubular secretion. Penicillins have wide therapeutic index. A high initial dose can be used.