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193 Cards in this Set
- Front
- Back
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What is Antibiosis?
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Inhibition of a microorganism by a substance actively produced by another microorganism
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What is Antibiotic?
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inhibition of microorganism by a substance that has been isolated, purified and standardized
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What is Antimicrobial?
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Antibiotic + any other chemical which can also inhibit the growth of the microorganism
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What is Empiric purpose vs. Therapeutic use?
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Empiric - given on suspicion of infection, before it's proven;
Therapeutic - use of antibiotic after infection is proven |
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MIC vs MBC
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MIC - Minimal inhibitory concentration least amount that inhibits growth
MBC - Minimal bactericidal concentration, east amount that kills organism, no cloudiness to agar plate |
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MBC/MIC ratio
cidal vs static |
Cidal - Ratio is small, <4
Static - Ratio is high, growth is inhibited but organism is not killed |
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What is subinhibitory effect?
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Drug concentration lower than the MIC may still slow the growth somewhat and/or produce structurally abnormal forms that makes it more susceptible to host defenses.
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What is post-antibiotic effect?
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The lag period after antibiotic exposure ends before organism regrowth - is important in deciding dosing intervals of the antibiotic.
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True or False. Most antibiotic penetrate intracellularly
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False. Site of infection often present penetration problems for many drugs
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List factors affecting host treatment
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Host immune deficits, Site of Infection, Local Factors, Patient's Age, Host variables affecting absorption/metabolism/elimination, allergy, interation with other meds
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List 8 Important Drug Variables
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Route of Administration
Dosage Penetration into sites (CNS, bone, etc) Routes/Rates of metabolism/excretion Protein Binding Chemical effect Toxicities - Allergy, GI upset, Organ Dysfunction Cost |
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What is the magic bullet concept?
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The effect of the antimicrobial is solely on the infecting/targetted organism and does nothing else to the normal flora
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What is the therapeutic/toxic ratio?
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The likelihood of therapeutic benefit compared to an adverse reaction
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Know properties of ideal antibiotics
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Magic bullet, excellent penetration to site of infection, effective PO, infrequent dosing, short course therapy, non-allergenic, nontoxic, well tolerated, no drug interactions, no adjustment needed for organ dysfunction, cheap
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What are the functions for bacterial cell wall? (3)
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surrounds cytoplasmic membrane
maintains shape of cell prevents cell lysis from high osmotic pressure |
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What is the main component of the bacterial cell wall?
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peptidoglycan located in periplasm
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Describe the peptidoglycan polymer
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-polysaccharides with alternating aminohexoses (N-acetylglucosamine, N-acetylmuramic acid)
-pentapeptide chains terminating in D-Ala-D-Ala + pentaglycine bridge |
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Describe the transpeptidation reaction
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a peptidoglycan polymer chain links with another one by removing the last alanine by carboxypeptidase and makes a peptide bond catalyzed by transpeptidase
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What is the enzyme that removes the terminating D-Ala?
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Carboxypeptidase
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What are 4 mechanism by which microbes develop resistance to antibiotics?
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-Inactivate drug
-Change structure of receptor/binding site -change in drug permeation/transport -alteration of metabolic pathways to bypass the activation of drug |
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Describe the structure of Penicillins
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4 membered B-lactam ring + 5 membered thiazolidine ring + side chain
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What determines the drug's stability to enzymatic/acidic hydrolysis and affects its antibacterial spectrum?
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Side chaine
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WWhat are PBPs?
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Receptors for B-lactam drugs.
B-lactams bind to PBPs and inhibit transpeptidation Binding of the drugs alter the shape of the bacterial cell |
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What is the mechanism of action for Penicillin Drugs? (3)
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D-Ala-D-Ala analogs that covalently bind PBPS, competitively inhibit transpeptidase, and activate autolysins
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Which bacteria modify target PBPs as a mechanism of resistance?
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methicillin-resistant Staph aureus (MRSA), methicillin-resistant Staph epidermis (MRSE) and Penicillin-resistant Streptococcus pneumoniae (PRSP)
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Which bacteria impairs penetration as a mechanism of resistance?
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Pseudomonas Aeruginosa
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What bacteria uses an efflux pump as a mechanism of resistance?
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Salmonella Typhimurium
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What are the narrow-spectrum penicillins? What are the resistant organisms?
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Penicillin G, Penicillin V
most staph aureus strains many N. gonorrhoeae strains |
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What are the very narrow spectrum penicillins(5)? What are the resistant organisms? What kind of infections are they used for?
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Methicillin, Nafcillin, oxacillin, cloxacillin, dicloxazillin
Resistant orgs: MRSA, MRSE, PRSP Used for Staph Aureus |
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Why are MRSA and PRSA resistant to penicillins?
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MRSA and PRSP are resistant bc they modify the binding protein. Penicinillase/Beta Lactamase is not the issue…
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What are the wider-spectrum penicillin drugs?
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Ampicillin, Amoxicillin, Ticarcillin, Piperacillin
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What class of drugs are synergistic with aminoglycosides?
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Penicillins
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What Beta-lactamase inhibitor is amoxicillin always paired with?
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Clavulanic acid
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What Beta-lactamase inhibitor is Ampicillin always paired with
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Sulbactam
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What Beta-lactamase inhibitor is Piperacillin always paired with?
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Tazobactam
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What Beta-lactamase inhibitor is Ticarcillin always paired with?
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Clavulanic Acid
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DDescribe the structure of Cephalosporins
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4 membered B-lactam ring + 6 membered dihydrothiazine ring + 2 side chains
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What is the mechanism of action for Cephalosporins?
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D-Ala-D-Ala analogs that bind PBPs, inhibit transpeptidase reaction and activate autolysins
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What are the mechanisms of resistance to cephalosporins
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inactivations by B-lactamases, modification of target PBPs, decrease in drug permeability
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Which drugs are first generation cephalosporins?(2)
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cefazolin
cephalexin |
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Which drugs are second generation cephalosporins(5)
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Cefaclor
cefotetan cefamandole cefoxitin cefuroxime |
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Which drugs are third generation cephalosporins?(5)
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cefotaxime
cefixime cefoperazone ceftriaxine ceftazidime |
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Which drug is the 4th generation cephalosporin?
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Cefepime
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Describe the difference between the generations of cephalosporin.
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From 1st -> 3rd: Decreasing gm + coverage, increasing gm - coverage, increase in CNS penetration, increasing resistance to B-lactamase,
4th Generation - gm + and gm - activity = wide spectrum |
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What is the only available monobactam in US?
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aztreonam
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What is the mechanism of action for monobactams?
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binds to specific PBP3
active against to certain gram - rods no activity against: gm + and anerobes synergistic with aminoglycosides |
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What is the structure of carbapenems?
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B-lactam ring + 5 membered penem ring
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Which antibiotics have the broadest spectrum? What are they useful for and what are the exceptions?
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Carbapenems
Useful for :gm + cocci, gm - rods, anerobes Exceptions: MRSA, L. monocytogenes |
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What are the Carbapenems? (4)
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Imipenem, Meropenem, Ertepenem, Doripenem
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What is the purpose of B-lactamase inhibitors?
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Themselves these arent drugs but they serve as competitive inhibitor to inhibit beta lactamase to make the drugs work better. Alone, they really don’t have good activity
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Vancomycin is synthesized from
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a glycopeptide from streptococcus orientalis
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What is the MOA of Vancomycin?
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Vancomycin binds firmly to D-Ala, D-Ala terminus and inhibits transglycosylase by sterically/physically hindering the elongation of peptidoglycan and cross-linking
-damages cytoplasmic membranes |
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What is the mechanism of resistance to vancomycin? What microbes do this?
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-Modification of D-ala-D-ala to d-ala-d-lactate (vancomycin-resistant enterococci, vancomycin-resistant staph aureus)
-Plasmid-mediacted changes in permeability to drug |
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What are the clinical uses for vancomycin? What is vancomycin ineffective for?
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CI: gm + bacterium, reserved for treating serious infections of MRSA and PRSP
Not useful for gm - bc it cannot enter the bacterial wall. |
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Which 2 Penicillins are best absorbed?
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Penicillin V
Amoxicillin |
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How are penicillins chiefly eliminated?
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By kidney. Primarily by tubular secretion
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How are the penicillinase resistant penicillins affected with renal insufficiency? liver insuffiency?
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renal - slighty affected, don't have to change does much
liver - yes! it's largely metabolized/excreted by liver |
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Where is it hard for penicillins to penetrate?
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Prostate, CNS, eye
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Penicillin is the treatment of choice for: (5)
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1. Streptococcal infections
2. Non - Penicillinase producing Staph Aureus infections 3. Many anaerobes 4. Neisseria meningitides 5.Treponemes |
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What are otitis media and sinusitis often treated with? What about bronchitis, pneumonia
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Ampicillin and amoxicillin
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Which penicillins are used intravenously? What are they commonly given with?
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-Ticarcillin and piperracilin
-Given with beta-lactamase inhibitors |
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Penicillins + aminoglycosides provide synergistic activity especially against what 2 organisms?
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Entercoccus Faecalis
Pseudomonas |
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What is the most common adverse reaction to penicillin?
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delayed onset rash (3-10 days)
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List 6 adverse reactions to penicillins
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-Allergy
-Diarrhea -Neuromuscular irritability -Hematologic changes -Drug fever -Interstitial nephritis |
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What are the most common adverse reactions for ampicillin/amoxicillin?
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skin rashm diarrhea, pseudomembranous colitis
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What are the most common adverse reactions for Methicillin?
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interstitial nephritis
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What are the most common adverse reactions for Nafcillin?
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phlebitis, neutropenia
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What are the most common adverse reactions for oxacillin? (2)
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elevated hepatic transaminases, neutropenia
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What are the most common adverse reactions for penicillin, procaine
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neurologic reactions and abnormal behavior
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What is amoxicillin/clavulanic acid combo used for?
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mainly upper and lower resp. infections where beta-lactamase producing H.flu or Moraxella is expected
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What is ampicillin/sulbactam combo used for?
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parenteral therapy for mixed aerobi/anaerobic organisms where high-resistant strains are not expected
-Ex: GI/GU infections and pneumonias |
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What are ticarcillin/clavulanic acid and piperacillin/tazobactam used for?
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Wide variety of infections, more effective against more gm-'s that ampicillin/sulbactam.
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Which 3 Cephalosporin drugs require less dosage adjustment in renal failure bc of significant clearance through biliary excretion?
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Cefotaxime
Cefaoperazone Ceftriaxone |
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Which Cephalosporin drugs can penetrate to the CSF to treat CNS infections?
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Cefuroxime and 3rd/4th Generation agents
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What is the drug of choice for clean surgical prophylaxic?
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First Generation Cephalosporin - Cefazolin, Cephalexin
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What are Cefoxitin and Cefotetan used for treatment/prophylaxis of?
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-Infections due to combo of anaerobes and community-origin aerobic organisms.
-Cost effective for intra-abdominal/pelvic infections where resistant strains are unlikely |
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Which Cephalosporins are drugs of choice for Meningitis?
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Ceftriaxone and Cefotaxime
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How long is Ceftriaxone's half-life? What is this drug useful for?
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8 Hours; useful for outpatient parenteral therapy
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What is Ceftazidine useful for? What can it be combined with to increase it's efficacy?
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"hospital-acquired" gram negatives including Pseudomonas and should be combined with aminoglycoside to prevent emergence of resistance
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What are fourth generation Cephalosporins useful for? What are they not?
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Very broad spectrum agents which are good for almost everything except
anaerobes, enterococci, Listeria and methicillin resistant staph – Thus useful for serious “hospital-acquired” infections. |
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What are second/third generation Cephalosportins clinically used for?
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mainly back up drugs for treating
respiratory infections where beta lactamase producing H.flu or Moraxella is known/suspected. Occasionally used for UTI. |
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How are the monobactam and carbapenem drugs administed?
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Only available via IV
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What is Imipenem combined with? What happens with it is combined?
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Imipenem is combined with a second compound – cilastatin – to block the action of dipeptidase in the renal tubule, thus allowing reasonable urinary concentrations of active drug.
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What is Aztreoname useful for?
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Treat serious gram negative infections but inactive against gram positives and all anerobes
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What drugs are "Ultimate broad spectrum antibiotics"?
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Imipenem, Meropenem, Doripenem, Ertapenem
Maybe useful in certain instances when shotgun is needed but should be replaced by more narrow spectrum therapy asap |
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Which carbepenem occasionally precipitates seizures in elderly or those with impaired renal function?
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Imipenem
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Why should Ceftriaxon be avoided in infants?
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gives more frequent diarrhea and can cause biliary sludge
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What is the spectrum for vancomycin?
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All gram positive bacteria but no activity against gram negative (can't get in) and not against vancomycin resistant enterococcus
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What are the uses for Vancomycin? (3)
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1) Staph/strep infections in patients allergic to Beta-lactam esp. Bacterial Endocarditis
2)For MRSA or PRSP 3) Pseudomembranous colitis due to toxin-producing clostridia |
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What toxicities are a/w vancomycin?
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Nephrotoxicity, Ototoxicity, hypersensitivity, cochlear and renal toxicity is dose related, red neck syndrome
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Qhat is "Red neck" syndrome?
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erythema, itching, hypotension when Vancomycin is infused too rapidly
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What is Telavancin?
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Derivatice of vancomycin
-Greater activity against resistant S. aureus -Longer half life (8 hrs) -Greater risk of nephrotoxicity -Contraindicated in Pregnancy |
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What is Daptomycin?
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A lipopeptide antibiotic for gram POSITIVE organism through action on cell membrane
-Concentration dependent killing -Long T1/2 - 9 hrs -Predominantly cleared by kidney |
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What is the main toxicity for Daptomycin?
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Skeletal Muscle - myalgias
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What is Daptomycin inactivated by?
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Lung surfactant
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What is the general mechanism of action of ribosomal antibiotics?
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They inhibit protein synthesis by binding to and interfering with ribosomes
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What size subunits do bacterial ribosomes have? Eukaryotic?
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Bacterial - 70s with 30s and 50s subunits
Eukaryotic - 80s with 40s and 60s subunits |
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What does selective toxicity mean with regards to ribosomal anitbiotics?
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Eukaryotic mitochondrial ribosomes somewhat resembles the bacterial ribosome, thus has some toxicities
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What enzyme is responsible for transfering amino acid to the growing peptide chain?
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peptidyl transferase
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Which drug classes bind to 30s ribosome?
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Spectinomycin, Aminoglycosides, Tetracyclines
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What drug classes binds to 50s ribosome unit?
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Chloramphenicol, Macrolides, Lincosamides, Streptogramins, Linezolid
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What is the mechanism of action for spectinomycin?
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Binds to 30s subunit and inhibits initiation complex
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What are the mechanisms of drug resistance for spectinomycin?
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-production of drug inactivating enzyme
-alteration of specific receptor on 30s subunit |
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List 6 Aminoglycoside Antibiotics
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Steptomycin, Gentamicin, Tobramycin, Neomycin, Amikacin, Netilmicin
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What is the MOA of Aminoglycosides?
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Binds to 30s subunit, blocks formation of 70s initiation complex, cause misreading of genetic code on mRNA template
-Prevent polysome formation - nonfunctional monosome -IRREVERSIBLY inhibits protein synthesis - bactericidal |
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How are aminoglycosides transported into cells?
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- Aminoglycosides are highly polar compounds.
- Initial event is passive diffusion via porin channels across the outer membrane. - Drug is then actively transported across the cell membrane into the cytoplasm by an oxygen-dependent process. The transmembrane electrochemical gradient supplies the energy for this process, and transport is coupled to a proton pump. |
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What inhibits transport of aminoglycosides? Why?
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low extracellular pH and anaerobic conditions reducing the transport gradient
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How is transport of Aminoglycoside drugs enhanced?
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Enhanced by cell wall-inhibiting drugs like B-lactam drugs
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What are the mechanisms of resistance for Aminoglycosides?
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-PRODUCE DRUG-INACTIVATING GROUP TRANSFERASES: (Aminoglycoside acetyltransferase, adenyltransferase, phosphotransferase)
-Alter 30s subunit -Alter permeability |
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How are aminoglycosides normally administered?
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Given IV or IM bc not absorbed by GI tract, neomycin is applied topically
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What are the adverse effects for aminoglycosides?
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Ototoxicity
Nephrotoxicity in elderly patients Neuromuscular blockade Skin Reactions |
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Aminoglycosides are indicated for what organisms?
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AEROBIC gram negatives; strict anaerobes are resistant bc oxygen is needed for uptake
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What drug class(es) bind to 30s to inhibit formation initiation complex?
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Spectinomycin
Aminoglycosides |
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What drug class inhibits binding of tRNA with amino acid?
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Tetracycline
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List 5 Tetracyclines
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Tetracycline
Doxycycline Minocycline Tigecycline Demeclocycline |
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What is the mechanism of action of tetracyclines?
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Binds to 20s subunit, inhibits binding of aminoacyl-tRNA to the mRNA ribosomal complex
Bacteriostatic |
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What is the mechanism of resistance for tetracycline?
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Effex portein pump
altered permeability to drug enzymatic inactivation of drug |
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What are the adverse effects for tetracycline?
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GI effects, Hepatotoxicity, Discoloration of teeth
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What are tetracyclines indicated for?
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Broad spectrum antibiotics
-Rickettsiae, chlamydiae, and mycoplasma infections |
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What is the mechanism of action for chloamphenicol?
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Binds 50s subunit and inhibits peptidyl transferrase in transpeptidation
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What is the mechanism of drug resistance for chloramphenicol?
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-Produces drug inactivating enzyme chloramphenicol acetyltransferase (Aminoglycosides also use this mechanism)
-Reduce permeability |
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What are the adverse effects of chloramphenicol? (3)
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Gray baby syndrome
BONE MARROW SUPPRESSION Anaplastic Anemia |
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What is Chloramphenicol indicated for?
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Broad spectrum
Typhoid fever Meningitis |
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List 4 Macrolides?
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Erythromycin, Clarithromycin, Azithromycin, Telithromycine
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What is the MOA of Macrolides
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Binds 50s subunit and prevents the ribsome from translocating down the mRNA
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What are the mechanisms of drug resistance for Macrolides?
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-METHYLATION of receptor on the 50s ribosome results in decreased affinity for drug
-Drug inactivating enzymes -reduced permeability to the drug |
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Which of Macrolides are more resistant to drug resistance?
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Telithromycin
-binds more tightly to ribosomes -poor substrate for efflux pumps |
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Which ribosomal antibiotics are poorly absorbed by GI tract?
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Spectinomycin
Aminoglycosides |
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Name 2 Lincosamides
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Lincomycin
Clindamycin |
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What is the mechanism of action for Lincosamides?
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Binds to 50s subunit and precents the ribosome from translocating down the mRNA
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What are the mechanisms of drug resistance for Lincosamides?
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-Methylation of ribosomal receptor site
-Production of drug inactivating enzymes -Reduced permeability to the drug |
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What are the adverse effect(s) of lincosamides?
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Diarrhea
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What are Lincosamides indicated for?
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Anaerobic infections
Aerobic gram (+) cocci infections |
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What is the mechanism of action for streptogramins?
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Bind to different sites on 50s ribosomal subunit; work synergistically to prevent the ribosome from translocating down mRNA
BACTERICIDAL |
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What are the mechanism of drug resistance in Streptogramins?
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Methylation of quinupristin binding site
Production of drug inactivating enzyme Active transport efflux |
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What are Streptogramins indicated for
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PRSP
MRSA VRSA VRE |
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What is the mechanism of action of Linezolid?
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Binds to a site on 23s rRNA of the 50s subunit - inhibits formation of 70s ribosome - inhibits initiation complex - inhibits translocation of peptidyl tRNA
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What is the mechanism of resistance for Linezolid?
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Mutation of the binding site on 23s rRNA
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What is Linezolid indicated for?
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PRSP
MRSA VRSA VRE |
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Which ribosomal antibiotics are bactericidal?
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Aminoglycosides
Linezolid Streptogramins |
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Which Ribosomal Antibiotics are inactivated by group transferase?
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Aminoglycosides
Chloramphenicol |
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Which Antibiotics use efflux protein pump
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Tetracycline
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Which drugs are inactivated by methylation?
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Macrolides
Lincosamides Streptogramins |
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Which aminoglycoside is given orally or topically?
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Neomycin
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DTrue or False. Dosage changes are required for renal insufficiency when using aminoglycosides.
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True
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Where does aminoglycosides poorly distribute to?
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CNS, Sputum, Bile, Prostate
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is the only clinical use for spectinomycin?
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Single dose tx for uncomplicated gonoccal infects when penicillinase-producing organisms are known or suspected
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Why is neomycin given orally?
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To decrease gut flora before GI surgery or in liver failure
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Which aminoglycoside is the lest susceptible to inactivating enzymes?
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Amikacin
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Do aminoglycosides have narrow or wide therapeutic/toxic ratio?
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Very Narrow
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With regards to aminoglycosides, what is nephrotoxicity related to?
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trough drug level
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Absorption of tetracyclines are inhibited by what?
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Food, especially milk, antacids, calcium and iron preparations
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Which tetracycline is NOT contraindicated in renal failure?
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Doxycycline
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What are the clinical indications for Tetracyclines? (6)
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Respiratory infections
STDs - chlamydia, PID, ureaplasma, chancroid Rickettsia infections Acne Lyme disease Drug resistant falciparum malaria |
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Why are tetracyclines contraindicated in pregnant women and children?
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administration of tetracycline should be withheld in pregnant women where it may cause depression of skeletal growth as well as impaired dentition in children up to the age of eight
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What is an toxicityy of Doxycyline?
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Esophageal ulcerations
Photosensitivity |
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What toxicity is a/w minocycline?
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Vertifo
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What can tetracyline and minocycline produce?
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Pre-renal azotemia
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What are the uses of tigecycline?
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Complicated skin/soft tissue infections
Complicated intra-abdominal infections |
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How is tigecyline administered and what is its half life?
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IV infusion
T1/2 - 36 hrs |
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What is Erythromycin indicated for?
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a) *Legionnaire’s disease
b) *Mycoplasma pneumoniae c) *Chlamydia infections d) *Corynebacterium diphtheriae e) *Bordetella pertussis f) *Campylobacter enteritis |
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What are the toxicities a/w Erythromycin?
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GI upset
Occasional cholestatic hepatitis hypersensistivity phlebitis with IV admin. Occasion cardiac rhythm disturbances |
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What is Telithromycin?
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Ketolides that ac on 50s ribosome to inhibit protein synthesis
-similar to macrolides except more active against strep pneumoniae, e. faecalis and s. aureus But has serious hepatotoxicity - rarely used |
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What is a toxicity of Clindamycin?
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Pseudomembranous colitis!! Caused by overgrowth of C. difficile
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What is the MOA of Mupirocin?
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A product of fermention of Pseudomonas Fluorescens; interfers with bacterial RNA and protein synthesis
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What are the clinical uses for Mupirocin?
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Topical tx of superficial skin infections due to staph and step
Nasal application to eliminate S. aureus |
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What is the MOA of rifaximin? What are its uses?
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Binds to Beta subunit of RNA polymeras to inhibit RNA synthesis
Uses: -Prevention/Tx of traveler's diarrhea -Prevention/Tx of hepatic encepholpathy -Tx of refractory C. Diff colitis |
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What is chloramphenicol still used for?
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Bacterial conjunctivitis
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What is the major serious side effect of chloramphenicol?
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Hematologic - bone marrow suppression; chloamphenicol decreases the incorporation of iron into hemoglobin
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What is the MOA for Sulfonamides?
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Interference with microbial folic acid synthesis by competing with PABA for incorporation into difydrofolic acid
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What are the mechanisms of bacterial resistance for Sulfas?
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-Mutation - produce increased PABA
-R-factor - decreased permeability of drug |
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:ist 2 Sulfa drugs? Which has the longest T1/2?
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Sulfisoazole
Sulfamethoxazole Sulfadiazine* |
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What are the clinical uses for sulfa drugs? (3)
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-Uncomplicated UTIs
-Nocardiosis -Toxoplasmosis |
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What are the toxicities a/w sulfa?
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Chemical - displaces other substances from albumin, crystalluria
GI upset Allergic |
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What is the MOA of Trimethoprim?
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Inhibition of bacterial dihydrofolate reductase
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What is the clinical use of Trimethoprim?
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UTI due to most common urinary pathogens
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What is Bactrim, Septra?
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Trimothoprim-Sulfamethoxazole
Fixed combo of 1:5 ratio |
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What is the mechanism of action for Bactrim?
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Sequential blocking in folic acid synthesis synergy. Often Cidal
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What is Bactrim used for?
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***UTIs***
Otitis media Acute exacerbation of chronic bronchitis Enteric infection Nocardiosis Pneumocystic jiroveci pneumonia |
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List 2 older quinolones
List 5 new quinolones |
Old - naladixic acid; cinoxacin
New - Norfloxacin, Ciprofloxacin, Ofloxavin, Levofloxavin, Moxifloxacin |
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What is the MOA for Quinolones?
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-Inhibits bacterial DNA gyrase
-Bactericidal |
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What are the mechanisms of resistance for quinolones?
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-Spontaneous mutations in bacterial chromosome
-alteration of DNA gyrase subunit -Alteration of permeability |
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All fluoroquinolones have good activity against what?
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gm - organisms
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What is Norfloxacin used for?
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UTI
Enteric infections |
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What are Ciprofloxan, ofloxavin, levofloxavin, moxifloxavin used for?
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UTI/Enteric Infections
Prostatits Respiratory tract |
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Which quinolone is most active against pseudomonas?
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Ciprofloxacin
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What are the common toxicities for quinolones?
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GI upset, CNS - headache/insomnia, sleep disturbances
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Which quinolone is most active against Strep. Pneumoniae?
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Moxifloxacin
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What is the MOA for Metronidazole
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Acts as an electron sink depriving the cell of required reducing equivalents
Cidal against anaerobic bacteria |
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What is the clinical indications for Metronidazole?
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Protozoal infections
Anaerobic infections Antibiotic - associated colitis due to c. difficile |
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What are the toxicities a/w with metronidazole?
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GI upsent and metallic tast
Central and Peripheral Neuropathy Disulfiram like reactions Contraindicated in preganancy and children |
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What is the MOA of Nitrofurantion?
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Cellular enzyme reduces drug which damages DNA
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What is the use of Nitrofurantion?
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Uncomplicated UTI
UTI prophylaxis |
