What is a beta-lactam (β-lactam) antibiotic?

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From the FDA Drug Label

This product should be given cautiously to penicillin and other beta-lactam agent-sensitive patients Amoxicillin is similar to penicillin in its bactericidal action against susceptible bacteria during the stage of active multiplication. It acts through the inhibition of cell wall biosynthesis that leads to the death of the bacteria Resistance to amoxicillin is mediated primarily through enzymes called beta-lactamases that cleave the beta-lactam ring of amoxicillin, rendering it inactive.

A beta-lactam antibiotic is a type of antibiotic that works by inhibiting cell wall biosynthesis in bacteria, leading to their death. It is characterized by the presence of a beta-lactam ring in its molecular structure. Examples of beta-lactam antibiotics include penicillins and cephalosporins, such as ceftriaxone and amoxicillin 1 2.

From the Research

Beta lactam antibiotics are a class of antibiotics that contain a beta-lactam ring in their molecular structure, including penicillins, cephalosporins, carbapenems, and monobactams, which work by inhibiting bacterial cell wall synthesis. This group includes penicillins (such as amoxicillin, ampicillin, and penicillin G), cephalosporins (like cefazolin, ceftriaxone, and cefepime), carbapenems (including meropenem, imipenem, and ertapenem), and monobactams (aztreonam) 3. These antibiotics work by inhibiting bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), which are enzymes involved in the final stage of bacterial cell wall formation. This disruption causes structural weakness in the bacterial cell wall, leading to cell lysis and death.

Key Characteristics of Beta Lactam Antibiotics

  • Effective against many gram-positive and some gram-negative bacteria
  • Resistance can develop through mechanisms like beta-lactamase production (enzymes that break down the beta-lactam ring), altered PBPs, or reduced permeability
  • Common side effects include allergic reactions (ranging from rashes to anaphylaxis), gastrointestinal disturbances, and occasionally nephrotoxicity
  • Cross-reactivity between different beta lactam classes can occur but varies significantly, with patients allergic to penicillins sometimes able to tolerate cephalosporins or carbapenems 4. The most recent and highest quality study on beta lactam antibiotics, published in 2020, provides a comprehensive overview of the different classes of beta-lactam antibiotics, their mechanism of action, and their spectrum of antimicrobial activity 3.

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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