Antibiotics Flashcards
[SATA] Which of the following agents inhibit synthesis or disrupt the bacterial cell wall?
A. Monobactams
B. Cycloserine
C. Vancomycin
A, B, C
Which of the following are beta lactic antibiotics? A. penicillins B. monobactams C. D. cephalosporins E. F. carbapenems
A, B, D, F
___________ Inhibits bacterial cell wall synthesis by binding to the penicillin binding proteins (PBP), which inhibits transpeptidation of the cell wall and activates autolysins, causing cell lysis.
Penicillins
Are penicillins bactericidal or bacteriostatic?
bactericidal
Are penicillins time dependent of concentration dependent killing agents?
time dependent
What are two ways bacteria can become resistant to penicillins?
- Destruction of beta-lactam ring by bacterial enzymes
* Inability to reach target PBPs
What are the 4 classes of penicillins?
- Natural
- Penicillinase resistant
- Amino-penicillins
- Extended spectrum
Name the 2 natural penicillins?
- Penicillin G
2. Penicillin V
Natural Penicillins are primarily Gram + or Gram - spectrum?
Gram +
__________ penicillins are degraded by acid and enzymes in stomach and therefore are not given orally
Natural
Which of the following are penicillinase resistant penicillins? A. Nafcillin B. Ampicillin C. Oxacillin D. Dicloxacillin E. Amoxicillin
A, C, D
What are 3 drugs that treat C diff?
Metronidazole
Oral Vancomycin
Fidaxomicin
List some complications of antibiotic therapy.
Mild GI disturbances Overgrowth of opportunistic infection Decreased efficacy of oral contraceptives increased bleeding antifungal or yeast infection C. diff
Which type of allergic reaction is T-cell mediated?
Type IV–delayed allergic reaction
Which type of allergic reaction is immune complex-mediated?
Type III allergic reaction
Which allergic reaction usually starts 5-21 days after initial drug exposure?
Type III allergic reaction
Which allergic reaction usually starts 2-7 days after initial drug exposure?
Type IV–delayed allergic reaction
What is the MOA of Bactrim?
Sulfonamide is a structural analog and competitive antagonist of PABA for bacterial synthesis of folic acid. Trimethoprim looks like dihydrofolic acid and competitively inhibits microbial dihydrofolate reductase (Bacteriostatic)
an antiprotozoal drug that treats gram negative anaerobic bacteria by entering cells which contain nitroreductase, where its nitro group is reduced into an unstable intermediate that bind to DNA and inhibits its synthesis causing cell death (bactericidal)
Metronidazole
What does Cimetidine do to metronidazole?
increases metronidazole’s levels
Spectrum of Natural penicillins?
Gram positive
Spectrum of penicillinase resistant?
Gram positive
Spectrum of Amino-penicillins?
GRAM POSITIVE & modest gram negative spectrum
Spectrum of extended-spectrum penicillins?
GRAM POSITIVE + Increased activity against GRAM NEGATIVE pseudomonas and proteus
Spectrum of First generation cephalosporins?
GRAM POSITIVE & modest gram negative spectrum (similar to amino-penicillins)
Spectrum of Second generation cephalosporins?
GRAM POSITIVE activity & increased activity against GRAM NEGATIVE (similar to amino-penicillins + ß-lactamase inhibitors)
Spectrum of Third generation cephalosporins?
GRAM POSITIVE + Increased activity against GRAM NEGATIVE pseudomonas and proteus
Spectrum of Fourth generation cephalosporins?
GRAM POSITIVE + Increased activity against GRAM NEGATIVE pseudomonas and proteus (like 3rd gen)
Spectrum of Fifth generation cephalosporins?
GRAM POSITIVE + Increased activity against GRAM NEGATIVE pseudomonas and proteus (like 3rd gen)
Which antibacterial inhibits bacterial cell wall synthesis by binding to penicillin binding proteins (PBP), which inhibits transpeptidation of the cell wall and activates autolysins causing cell lysis?
Penicillins & cephalosporins:
Which antibacterial inhibits the 2nd stage of bacterial cell wall synthesis by binding to the D-alanyl D-alanine portion of the precursor. Also alters membrane permeability & RNA synthesis (bactericidal)?
Vancomycin
Which antibacterial inhibits cell wall synthesis like Vancomycin (synthetic derivative of vanc) (bactericidal)?
Lipoglycopeptides
Which antibacterial inhibits bacterial cell wall synthesis, leading to cell lysis and death (bactericidal)
Bacitracin
Which antibacterial suggested that it inhibits synthesis of mycolic acid, a component of mycobacterial cell wall (bactericidal)?
Isoniazid
Which antibacterial inhibits cell wall synthesis by acting like an alanine analog and interferes with 2 steps in peptidoglycan synthesis (causes competitive inhibition but not complete cell wall inhibition) (bacteriostatic)?
Cycloserine
binds to bacterial cell membrane which disrupts membrane structure and increases permeability (bactericidal)
Polymixin B & Colistimethate
binds to bacterial membranes and causes a rapid depolarization of membrane potential. The loss of membrane potential leads to inhibition of protein, DNA, and RNA synthesis, which results in bacterial cell death
(makes cell “leaky”) (bactericidal)
Daptomycin (Cubicin)
Bacteria reduces the drug into an intermediate which inhibits bacterial process (bacteriostatic)
Nitrofurantoin
Which drugs bind 50S ribosomal subunit and alter protein synthesis?
Chloramphenicol Macrolide Antibiotics (Erythromycin, Clarithromycin, Azithromycin, Fidaxomicin) Ketolide (Telithromycin (Ketek)) Lincosamides (Lincomycin, Clindamycin) Oxalodinones (Linezolid, Tedezolid) Streptogramins (Quinupristin/dalfopristin (Synercid))
Which drugs bind 30S ribosomal subunit and alter protein synthesis?
Tetracyclines
Glycylcyclines
Aminoglycosides
What are the agents that affect nucleic acid metabolism?
Rifamycins
Quinolones
Metronidazole
Bactericidal or bacteriostatic?
Beta-lactam Abx
Bactericidal
Bactericidal or bacteriostatic?
Vancomycin
Bactericidal
Bactericidal or bacteriostatic?
Lipoglycopeptides
Bactericidal
Bactericidal or bacteriostatic?
Bacitracin
Bactericidal
Bactericidal or bacteriostatic?
Isoniazid
Bactericidal
Bactericidal or bacteriostatic?
Detergents: polymyxin, colistimethate
Bactericidal
Bactericidal or bacteriostatic?
Lipopetides: Daptomycin
Bactericidal
Bactericidal or bacteriostatic?
Polyene antifungal agents: nystatin, amphotericin B
Bactericidal
Bactericidal or bacteriostatic?
Streptogramins: Quinupristin + dalfopristin (Synercid)
combined are cidal, separate are static
Bactericidal or bacteriostatic?
Oxalodinones
Linezolid
Bactericidal against streptococci & vanc-resistant enterococcus (VRE)
Bacteriostatic against enterococci & staphylococci (including MRSA)
Bactericidal or bacteriostatic?
Aminoglycosides
Bactericidal
Bactericidal or bacteriostatic?
Metronidazole
Bactericidal
Bactericidal or bacteriostatic?
Cycloserine
bacteriostatic