<prompt> All of the following are true about Penicillins except?Penicillin V is acid stable, can be given orallyProbenecid increases the duration of action by penicillinsBenzathine penicillin is used in the treatment of NeurosyphilisPenicllin V acts mainly on gram ve micro organisms  <response>: Aqueous penicillin can cross BBB and hence it is the drug of choice in patients of neurosyphilis. 