What does 'penicillin (Penicillin) G (Gram)' sensitivity mean on a culture report?

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From the FDA Drug Label

Penicillin G is bactericidal against penicillin-susceptible microorganisms during the stage of active multiplication It acts through the inhibition of biosynthesis of cell-wall peptidoglycan rendering the cell wall osmotically unstable. Penicillin G is highly active in vitro against streptococci (groups A, B, C, G, H, L, and M) and Neisseria meningitidis Other organisms susceptible in vitro to penicillin G are Neisseria gonorrhoeae,Corynebacterium diphtheriae, Bacillus anthracis, clostridia, Actinomyces species, Spirillum minus, Streptobacillus moniliformis, Listeria monocytogenes, and leptospira;Treponema pallidum is extremely susceptible

The term 'penicillin G's' in culture sensitivity likely refers to the susceptibility of certain microorganisms to penicillin G.

  • 's' may denote susceptible, indicating that the microorganism is sensitive to penicillin G.
  • This means that penicillin G can effectively inhibit the growth of or kill the microorganism.
  • The FDA drug label provides information on the susceptibility of various microorganisms to penicillin G, including streptococci, Neisseria meningitidis, and Treponema pallidum 1, 1.

From the Research

When a culture sensitivity report says "penicillin G S," it means the bacteria is sensitive to penicillin G, indicating this antibiotic would be effective for treating the infection. This is based on the most recent evidence from 2, which although not directly related to the question of what "penicillin G S" means, supports the use of penicillin G in certain clinical contexts, underscoring its efficacy against sensitive bacteria. The "S" stands for "sensitive," meaning the bacteria will likely respond well to treatment with this antibiotic at standard dosages, as opposed to "R" (resistant) or "I" (intermediate sensitivity) 3. Penicillin G is an older, injectable form of penicillin that works by interfering with bacterial cell wall synthesis, causing the bacteria to rupture and die, as described in 4. If your doctor prescribes penicillin G based on this sensitivity, it's typically administered as an injection, often in doses of 2-4 million units every 4-6 hours for serious infections, with treatment duration depending on the type and severity of infection. Some key points to consider include:

  • Completing the full course of antibiotics even if symptoms improve before finishing treatment.
  • Disclosing any penicillin allergies to healthcare providers before starting treatment, as highlighted by the consideration of beta-lactam allergies in 2.
  • Being aware that while penicillin G is effective against a range of bacteria, resistance patterns can vary, and the choice of antibiotic should always be guided by culture sensitivity results and clinical judgment, supported by studies like 5 that compare the effectiveness of different antibiotics.

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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