All of the following statements regarding penicillin-G are true, EXCEPT:
Can be given orally
Active against gram positive organisms
Probenecid given along with penicillin-G increases its duration of action
Acts by inhibition of cell wall synthesis
Penicillin G is acid labile and it is destroyed easily by gastric acid, and hence it can only be given parenterally (intravenously or intramuscularly) and not orally. Ref: KDT, 6th Edition, Pages 696-97 ; Streptococcal Pharyngitis: Optimal Management By Jean Claude Pechere, 3rd Volume, Page 188 ; Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk By Gerald Briggs, Roger K. Freeman, Sumner J. Yaffe, Page 205