Sherris Medical Microbiology, 7e >Antibacterial Agents and Resistance Kenneth J. Ryan+ TABLE 23–1Characteristics of Antibacterial Drugs TARGET/REPRESENTATIVE DRUGS CHARACTERISTICS Cell Wall Synthesis β-Lactams Bactericidal against a variety of bacteria; inhibit penicillin-binding proteins Penicillins Natural penicillins: penicillin G, penicillin V Active against gram-positive bacteria and some gram-negative cocci Penicillinase-resistant: methicillin, dicloxicillin Similar to the natural penicillins, but resistant to inactivation by the penicillinase of staphylococci Broad-spectrum: ampicillin, amoxicillin Similar to the natural penicillins, but more active against gram-negative organisms Extended-spectrum: ticarcillin, piperacillin Increased activity against gram-negative rods, including Pseudomonas species, and anaerobes including Bacteroides fragilis. Usually combined with beta-lactamase inhibitors Cephalosporins Some are more effective against gram-negative bacteria and less susceptible to destruction by βlactamases Cephalexin, cefoxitin, ceftriaxone, cefepime, ceftaroline, ceftolozane Carbapenems Resistant to inactivation by β-lactamases. Many gram-positive and gram-negative bacteria including anaerobes are susceptible Imipenem, meropenem, doripenem, ertapenem Monobactams Resistant to β-lactamases. Purely gram-negative coverage, primarily active against members of the family Enterobacteriaceae Aztreonam Non–β-Lactams Vancomycin, teicoplanin, telavancin Bactericidal against gram-positive bacteria Bacitracin Bactericidal against gram-positive bacteria Protein Synthesis Aminoglycosides Bactericidal against gram-negative aerobic and facultative bacteria Gentamicin, tobramycin Tetracyclines Bacteriostatic against some gram-positive and gram-negative bacteria Tetracycline, doxycycline, inocycline Chloramphenicol Bacteriostatic and broad spectrum Macrolides Bacteriostatic against many gram-positive bacteria as well as some mycobacteria Erythromycin, clarithromycin, azithromycin Lincosamides Bacteriostatic against a variety of gram-positive and gram-negative bacteria, including anaerobes Clindamycin Oxazolidinones Bacteriostatic against a variety of gram-positive bacteria and mycobacteria Linezolid Streptogramins A synergistic combination of two drugs that bind to two different ribosomal sites. Individually each drug is bacteriostatic, but together they are bactericidal. Effective against a variety of gram-positive bacteria, including Enterococcus faecium Quinupristin, dalfopristin Nucleic Acid Synthesis Fluoroquinolones Bactericidal against a wide variety of gram-positive and gram-negative bacteria Ciprofloxacin, levofloxacin, moxifloxacin Rifamycins Bactericidal against gram-positive and some gram-negative bacteria. Often used to treat infections caused by Mycobacterium tuberculosis and as prophylaxis for close exposure to Neisseria meningitidis Rifampin, rifaximin, rifapentine Folate Biosynthesis Sulfonamides Bacteriostatic against a variety of gram-positive and gram-negative bacteria Trimethoprim Often used in combination with a sulfa drug for a synergistic effect Cell Membrane Integrity Polymyxin B, colistin Bactericidal against gram-negative cells by damaging cell membranes Daptomycin Bactericidal against gram-positive bacteria Date of download: 06/04/22 from AccessMedicine: accessmedicine.mhmedical.com, Copyright © McGraw Hill. All rights reserved.