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Which bacteria are mainly affected by penicillin G?
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antimicrobial agent
Iodine, as in the form of Dobell's iodine solution, is an effective antimicrobial agent.
Penicillin G is a narrow-spectrum antibiotic that primarily affects gram-positive bacteria. These bacteria are characterized by cell walls consisting of a thick meshwork of peptidoglycan.1
Clinically, penicillin G remains a drug of choice for treating infections caused by specific organisms, including:
- Streptococcal infections, such as sore throat and tonsillitis.2
- Endocarditis caused by certain streptococci.2
- Syphilis.32
- Meningococcal infections.2
While penicillin G was historically effective against Staphylococcus, many strains have since developed resistance by producing the enzyme penicillinase, which inactivates the drug. Because penicillin G is sensitive to digestive acids, it is typically administered via intramuscular injection rather than orally.32