Penicillin is an antibacterial medication that is used to treat or prevent infections that are strongly suspected or proven to be caused by bacteria, especially microorganisms susceptible to penicillin. Penicillin V’s mechanism of action is interfering with the cell wall synthesis of microorganisms sensitive to penicillin during replication. Historically, penicillin has been indicated to treat susceptible Streptococcal infections (e.g. strep throat), Pneumococcal infections and Staphylococcal infections. Penicillin is structurally similar to a number of other antibacterial medications such as amoxicillin. For many types of infections, the use of penicillin has been replaced by cephalosporins such as cephalexin and cefdinir due to antibiotic resistance.