What are the categories of antibiotics?

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From the Guidelines

Antibiotics can be broadly categorized into several classes, including beta-lactams (such as penicillins and cephalosporins), macrolides, fluoroquinolones, tetracyclines, aminoglycosides, sulfonamides, glycopeptides, oxazolidinones, and carbapenems, with each class having a distinct mechanism of action and spectrum of activity. The main categories of antibiotics are:

  • Beta-lactams, which include penicillins (amoxicillin, penicillin G) and cephalosporins (cefazolin, ceftriaxone), and work by inhibiting bacterial cell wall synthesis 1
  • Macrolides (azithromycin, erythromycin), which interfere with protein synthesis
  • Fluoroquinolones (ciprofloxacin, levofloxacin), which inhibit DNA replication
  • Tetracyclines (doxycycline, minocycline), which also interfere with protein synthesis
  • Aminoglycosides (gentamicin, tobramycin), which interfere with protein synthesis
  • Sulfonamides (sulfamethoxazole), which block folic acid synthesis
  • Glycopeptides (vancomycin), which inhibit bacterial cell wall synthesis
  • Oxazolidinones (linezolid), which interfere with protein synthesis
  • Carbapenems (meropenem, imipenem), which inhibit bacterial cell wall synthesis The choice of antibiotic depends on various factors, including the suspected pathogen, infection site, patient allergies, local resistance patterns, and patient factors like kidney function, as highlighted in the guidelines for skin and soft tissue infections 1. Some key points to consider when selecting an antibiotic include:
  • The severity of the infection, with more severe infections requiring broader-spectrum antibiotics
  • The presence of underlying medical conditions, such as kidney disease, which may affect antibiotic choice
  • The potential for antibiotic resistance, which can be mitigated by using narrower-spectrum antibiotics when possible
  • The need for culture and sensitivity testing to guide antibiotic selection, as recommended by the Infectious Diseases Society of America guidelines 1.

From the FDA Drug Label

Fluoroquinolones, including levofloxacin, differ in chemical structure and mode of action from aminoglycosides, macrolides and β-lactam antibiotics, including penicillins The categories of antibiotics mentioned are:

  • Fluoroquinolones (e.g., levofloxacin)
  • Aminoglycosides
  • Macrolides
  • β-lactam antibiotics (including penicillins) 2

From the Research

Categories of Antibiotics

The main categories of antibiotics include:

  • β-Lactam antibiotics, which are one of the most relevant drug classes of antibacterial agents worldwide 3, 4, 5
  • Aminoglycoside antibiotics, which can be used in combination with other antibiotics such as β-lactams or plectasin to treat methicillin-sensitive and methicillin-resistant Staphylococcus aureus 6
  • Glycopeptide antibiotics, which can be used to treat various bacterial infections, but may not always show synergistic effects when combined with other antibiotics such as plectasin 6

Subcategories of β-Lactam Antibiotics

The subcategories of β-lactam antibiotics include:

  • Penicillins, which are one of the earliest discovered β-lactam antibiotics 3, 4, 5
  • Cephalosporins, which are semi-synthetic β-lactam antibiotics that can be used to treat a wide range of bacterial infections 3, 4, 7
  • Carbapenems, which are broad-spectrum β-lactam antibiotics that can be used to treat serious bacterial infections 3, 4
  • Monobactams, which are a class of β-lactam antibiotics that can be used to treat certain types of bacterial infections 3, 4
  • Penems, which are a class of β-lactam antibiotics that can be used to treat certain types of bacterial infections 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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