Antimicrobials Flashcards
Penicillin G
Prototype β-lactam antibiotic. IV.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes.
Mostly used for gram-positive organisms (S. pneumoniae, S. pyogenes, Actinomyces). Also used for N. meningitidis, T. pallidum. BacteriCIDAL for gram-positive cocci, gram-positive rods, gram-negative cocci, and spirochetes. Penicillinase sensitive.
Hypersensitivity reactions, hemolytic anemia. Safe in pregnancy.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Penicillin V
Prototype β-lactam antibiotic. Oral.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes.
Mostly used for gram-positive organisms (S. pneumoniae, S. pyogenes, Actinomyces). Also used for N. meningitidis, T. pallidum. BacteriCIDAL for gram-positive cocci, gram-positive rods, gram-negative cocci, and spirochetes. Penicillinase sensitive.
Hypersensitivity reactions, hemolytic anemia. Safe in pregnancy.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Ampicillin
Aminopenicillin, penicillinase-sensitive penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes.
Extended spectrum. BacteriCIDAL for Haemophilus influenzae, E. coli, Listeria monocytogenes, Proteus mirabilis, Salmonella, Shigella, enterococci. Penicillinase sensitive. Combine with clavulanic acid to protect against β-lactamase.
Hypersensitivity reactions, rash, pseudomembranous colitis.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Amoxicillin
Aminopenicillin, penicillinase-sensitive penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes.
Extended spectrum. BacteriCIDAL for Haemophilus influenzae, E. coli, Listeria monocytogenes, Proteus mirabilis, Salmonella, Shigella, enterococci. Penicillinase sensitive. Combine with clavulanic acid to protect against β-lactamase.
Hypersensitivity reactions, rash, pseudomembranous colitis.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Oxacillin
Penicillinase-resistant penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. Penicillinase resistant because bulky R group blocks access of β-lactamase to β-lactam ring.
Narrow spectrum. BacteriCIDAL for S. aureus (except MRSA; resistant due to altered penicillin-binding protein target site).
Hypersensitivity reactions, interstitial nephritis.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Nafcillin
Penicillinase-resistant penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. Penicillinase resistant because bulky R group blocks access of β-lactamase to β-lactam ring.
Narrow spectrum. BacteriCIDAL for S. aureus (except MRSA; resistant due to altered penicillin-binding protein target site).
Hypersensitivity reactions, interstitial nephritis.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Dicloxacillin
Penicillinase-resistant penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. Penicillinase resistant because bulky R group blocks access of β-lactamase to β-lactam ring.
Narrow spectrum. BacteriCIDAL for S. aureus (except MRSA; resistant due to altered penicillin-binding protein target site).
Hypersensitivity reactions, interstitial nephritis.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Methicillin
Penicillinase-resistant penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. Penicillinase resistant because bulky R group blocks access of β-lactamase to β-lactam ring.
Narrow spectrum. BacteriCIDAL for S. aureus (except MRSA; resistant due to altered penicillin-binding protein target site).
Hypersensitivity reactions, interstitial nephritis.
Resistance conveyed by penicillinase in bacteria (a type of β-lactamase), which cleaves the β-lactam ring.
Ticaricillin
Anti-pseudomonal penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes.
Extended spectrum. BacteriCIDAL for Pseudomonas species, gram-negative rods. Susceptible to penicillinase. Use with β-lactamase inhibitors.
Hypersensitivity reactions.
Piperacillin
Anti-pseudomonal penicillin.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes.
Extended spectrum. BacteriCIDAL for Pseudomonas species, gram-negative rods. Susceptible to penicillinase. Use with β-lactamase inhibitors.
Hypersensitivity reactions.
Clavulanic acid
β-lactamase inhibitor.
Added to penicillin antibiotics to protect the antibiotic from destruction by β-lactamase (a penicillinase)
Sulbactam
β-lactamase inhibitor.
Added to penicillin antibiotics to protect the antibiotic from destruction by β-lactamase (a penicillinase)
Tazobactam
β-lactamase inhibitor.
Added to penicillin antibiotics to protect the antibiotic from destruction by β-lactamase (a penicillinase)
Cefazolin
First generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Gram-positive cocci, Proteus mirabilis, E. coli, Klebsiella pneumoniae. Used prior to surgery to prevent S. aureus wound infections.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increase the nephrotoxicity of aminoglycosides. Safe in pregnancy.
Cephalexin
First generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Gram-positive cocci, Proteus mirabilis, E. coli, Klebsiella pneumoniae.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increase the nephrotoxicity of aminoglycosides. Safe in pregnancy.
Cefoxitin
Second generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Gram-positive cocci, Haemophilus influenzae, Enterobacter aerogenes, Neisseria species, Proteus mirabilis, E. coli, Klebsiella pneumoniae, Serratia marcescens.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increase the nephrotoxicity of aminoglycosides. Safe in pregnancy.
Cefaclor
Second generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Gram-positive cocci, Haemophilus influenzae, Enterobacter aerogenes, Neisseria species, Proteus mirabilis, E. coli, Klebsiella pneumoniae, Serratia marcescens.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increase the nephrotoxicity of aminoglycosides. Safe in pregnancy.
Cefuroxime
Second generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Gram-positive cocci, Haemophilus influenzae, Enterobacter aerogenes, Neisseria species, Proteus mirabilis, E. coli, Klebsiella pneumoniae, Serratia marcescens.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increase the nephrotoxicity of aminoglycosides. Safe in pregnancy.
Ceftriaxone
Third generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Serious gram-negative infections resistant to other β-lactams. Meningitis, gonorrhea.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increases nephrotoxicity of ahminoglycosides. Safe in pregnancy.
Cefotaxime
Third generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Serious gram-negative infections resistant to other β-lactams.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increases nephrotoxicity of ahminoglycosides. Safe in pregnancy.
Ceftazidime
Third generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Serious gram-negative infections resistant to other β-lactams. Pseudomonas.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increases nephrotoxicity of ahminoglycosides. Safe in pregnancy.
Cefipime
Fourth generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Increased activity against Pseudomonas and gram-positive organisms.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increases nephrotoxicity of ahminoglycosides. Safe in pregnancy.
Ceftaroline
Fifth generation cephalosporin. β-lactam drug.
Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Broad gram-positive and gram-negative organism coverage, including MRSA. Does not cover Pseudomonas.
Hypersensitivity reactions, vitamin K deficiency, low cross-reactivity with penicillins, increases nephrotoxicity of ahminoglycosides. Safe in pregnancy.
Aztreonam
Monobactam. Resistant to β-lactamases. Prevents peptidoglycan cross-linking by binding to penicillin-binding protein 3. Synergistic with aminoglycosides.
Gram-negative rods only. No activity against gram-positives or anaerobes. Useful in penicillin-allergic patients (no cross-allergenicity with penicillins) and those with renal insufficiency who cannot tolerate aminoglycosides.
Usually nontoxic. Occasional GI upset.
Imipenem
Broad spectrum, β-lactamase-resistant carbapenem. Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL. Always administered with cilastatian (inhibitor of renal dehydropeptidase I) to decrease inactivation of drug in renal tubules.
Gram-positive cocci, gram-negative rods, anaerobes. Wide spectrum, use is limited to life-threatening infections after other drugs have failed.
GI distress, skin rash, CNS toxicity (seizures) at high plasma levels.
Meropenem
Broad spectrum, β-lactamase-resistant carbapenem. Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL.
Gram-positive cocci, gram-negative rods, anaerobes. Wide spectrum, use is limited to life-threatening infections after other drugs have failed.
GI distress, skin rash, decreased risk of seizures. Stable to dehydropeptidase I.
Ertapenem
Broad spectrum, β-lactamase-resistant carbapenem. Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL. Always administered with cilastatian (inhibitor of renal dehydropeptidase I) to decrease inactivation of drug in renal tubules.
Gram-positive cocci, gram-negative rods, anaerobes. Wide spectrum, use is limited to life-threatening infections after other drugs have failed. Limited Pseudomonas coverage.
GI distress, skin rash, CNS toxicity (seizures) at high plasma levels.
Doripenem
Broad spectrum, β-lactamase-resistant carbapenem. Binds penicillin-binding proteins (transpeptidases), block transpeptidase cross-linking of peptidoglycan, activates autolytic enzymes. BacteriCIDAL. Always administered with cilastatian (inhibitor of renal dehydropeptidase I) to decrease inactivation of drug in renal tubules.
Gram-positive cocci, gram-negative rods, anaerobes. Wide spectrum, use is limited to life-threatening infections after other drugs have failed.
GI distress, skin rash, CNS toxicity (seizures) at high plasma levels.
Vancomycin
Inhibits cell wall peptidoglycan formation by binding D-ala D-ala portion of cell wall precursors. BacteriCIDAL.
Gram positive only. Serious, MDR organisms, including MRSA, enterococci, Clostridium difficile (oral dose for pseudomembranous colitis).
Well tolerated in general. Risk of nephrotoxicity, ototoxicity, thrombophlebitis, diffuse flushing (red man syndrome - prevent with antihistamines, slow infusion rate).
Resistance conveyed by modification of D-ala D-ala to D-ala D-lac.
Gentamicin
Aminoglycoside
Protein synthesis inhibitor at 30S ribosomal subunit. Inhibits formation of initiation complex and causes misreading of mRNA. Also blocks translocation. BacteriCIDAL.
Severe gram negative rod infections. Synergistic with β-lactam antibiotics. Requires O2 for uptake into cell, therefore ineffective against anaerobes.
Nephrotoxicity (especially when used with cephalosporins), neuromuscular blockade, ototoxicity (especially when used with loop diuretics), teratogen.
Resistance conveyed by bacterial transferase enzymes, which inactivate the drug by acetylation, phosphorylation, or adenylation.
Neomycin
Aminoglycoside
Protein synthesis inhibitor at 30S ribosomal subunit. Inhibits formation of initiation complex and causes misreading of mRNA. Also blocks translocation. BacteriCIDAL.
Severe gram negative rod infections. Synergistic with β-lactam antibiotics. Requires O2 for uptake into cell, therefore ineffective against anaerobes. Prophylactic for bowel surgery.
Nephrotoxicity (especially when used with cephalosporins), neuromuscular blockade, ototoxicity (especially when used with loop diuretics), teratogen.
Resistance conveyed by bacterial transferase enzymes, which inactivate the drug by acetylation, phosphorylation, or adenylation.
Amikacin
Aminoglycoside
Protein synthesis inhibitor at 30S ribosomal subunit. Inhibits formation of initiation complex and causes misreading of mRNA. Also blocks translocation. BacteriCIDAL.
Severe gram negative rod infections. Synergistic with β-lactam antibiotics. Requires O2 for uptake into cell, therefore ineffective against anaerobes.
Nephrotoxicity (especially when used with cephalosporins), neuromuscular blockade, ototoxicity (especially when used with loop diuretics), teratogen.
Resistance conveyed by bacterial transferase enzymes, which inactivate the drug by acetylation, phosphorylation, or adenylation.
Tobramycin
Aminoglycoside
Protein synthesis inhibitor at 30S ribosomal subunit. Inhibits formation of initiation complex and causes misreading of mRNA. Also blocks translocation. BacteriCIDAL.
Severe gram negative rod infections. Synergistic with β-lactam antibiotics. Requires O2 for uptake into cell, therefore ineffective against anaerobes.
Nephrotoxicity (especially when used with cephalosporins), neuromuscular blockade, ototoxicity (especially when used with loop diuretics), teratogen.
Resistance conveyed by bacterial transferase enzymes, which inactivate the drug by acetylation, phosphorylation, or adenylation.
Streptomycin
Aminoglycoside
Protein synthesis inhibitor at 30S ribosomal subunit. Inhibits formation of initiation complex and causes misreading of mRNA. Also blocks translocation. BacteriCIDAL.
Severe gram negative rod infections. Synergistic with β-lactam antibiotics. Requires O2 for uptake into cell, therefore ineffective against anaerobes.
Nephrotoxicity (especially when used with cephalosporins), neuromuscular blockade, ototoxicity (especially when used with loop diuretics), teratogen.
Resistance conveyed by bacterial transferase enzymes, which inactivate the drug by acetylation, phosphorylation, or adenylation.
Tetracycline
Tetracycline
Protein synthesis inhibitor at 30S ribosomal subunit, prevents attachment of ammoniacal-tRNA. BacterioSTATIC.
Borrelia burgdorferi, M. pneumoniae. Ability to accumulate intracellularly makes it very effective against Rickettsia and Chlamydia. Also used to treat acne. Limited CNS penetration. Do not take with milk, antacids, or iron-containing preparations because divalent cations inhibit its absorption in the gut.
GI distress, discoloration of teeth, inhibition of bone growth in children. Photosensitivity. Contraindicated in pregnancy.
Resistance conveyed by decreased uptake or increased efflux out of bacterial cells by plasmid-encoded transport pumps.
Doxycycline
Tetracycline
Protein synthesis inhibitor at 30S ribosomal subunit, prevents attachment of ammoniacal-tRNA. BacterioSTATIC.
Borrelia burgdorferi, M. pneumoniae. Ability to accumulate intracellularly makes it very effective against Rickettsia and Chlamydia. Also used to treat acne. Limited CNS penetration. Do not take with milk, antacids, or iron-containing preparations because divalent cations inhibit its absorption in the gut. Fecally eliminated, so safe in renal failure.
GI distress, discoloration of teeth, inhibition of bone growth in children. Photosensitivity. Contraindicated in pregnancy.
Resistance conveyed by decreased uptake or increased efflux out of bacterial cells by plasmid-encoded transport pumps.
Minocycline
Tetracycline
Protein synthesis inhibitor at 30S ribosomal subunit, prevents attachment of ammoniacal-tRNA. BacterioSTATIC.
Borrelia burgdorferi, M. pneumoniae. Ability to accumulate intracellularly makes it very effective against Rickettsia and Chlamydia. Also used to treat acne. Limited CNS penetration. Do not take with milk, antacids, or iron-containing preparations because divalent cations inhibit its absorption in the gut.
GI distress, discoloration of teeth, inhibition of bone growth in children. Photosensitivity. Contraindicated in pregnancy.
Resistance conveyed by decreased uptake or increased efflux out of bacterial cells by plasmid-encoded transport pumps.
Azithromycin
Macrolide
Inhibits protein synthesis by blocking translocation. Binds to 23S rRNA of the 50S ribosomal subunit. BacterioSTATIC.
Atypical pneumonias (Mycoplasma, Chlamydia, Legionella), STDs (Chlamydia) and gram positive cocci (streptococcal infections in patients allergic to penicillin).
GI motility issues, arrhythmia (prolonged QT), acute cholestatic hepatitis, rash, eosinophilia. Increases serum concentration of theophylline and anticoagulants.
Resistance conveyed by methylation of 23S rRNA-binding site, which prevents binding of drug.
Clarithromycin
Macrolide
Inhibits protein synthesis by blocking translocation. Binds to 23S rRNA of the 50S ribosomal subunit. BacterioSTATIC.
Atypical pneumonias (Mycoplasma, Chlamydia, Legionella), STDs (Chlamydia) and gram positive cocci (streptococcal infections in patients allergic to penicillin).
GI motility issues, arrhythmia (prolonged QT), acute cholestatic hepatitis, rash, eosinophilia. Increases serum concentration of theophylline and anticoagulants.
Resistance conveyed by methylation of 23S rRNA-binding site, which prevents binding of drug.
Erythromycin
Macrolide
Inhibits protein synthesis by blocking translocation. Binds to 23S rRNA of the 50S ribosomal subunit. BacterioSTATIC.
Atypical pneumonias (Mycoplasma, Chlamydia, Legionella), STDs (Chlamydia) and gram positive cocci (streptococcal infections in patients allergic to penicillin).
GI motility issues, arrhythmia (prolonged QT), acute cholestatic hepatitis, rash, eosinophilia. Increases serum concentration of theophylline and anticoagulants.
Resistance conveyed by methylation of 23S rRNA-binding site, which prevents binding of drug.
