Antibiotics: Others Flashcards
Flouroquinolones MOA
inhibit DNA gyrase and topoisomeraze IV. DNA can’t be replicated. Bactericidal.
Flouroquinolone Spectrum
Aerobic gram negative rods and some gram positive coverage (MRSA). Wide tissue distribution and penetration.
Ciprofloxacin (Cipro)
Flouroquinolone. Oral. antipsuedomonal.
Norfloxacin (noroxin)
Flouroquinolone. Oral. Prostatitis.
Ofloxacin (floxin)
Flouroquinolone. Oral. Prostatitis.
Levofloxacin (levaquin)
Flouroquinolone. Oral
Moxifloxacin (Avelox)
Flouroquinolone. Oral. anaerobes.
Gatifloxacin (tequin)
Flouroquinolone. Ocular application only.
Gemifloxacin (factive)
Flouroquinolone. Oral. Anaerobes.
Anthrax prophylaxis DOC
Cipro.
Pseudomonas aerginosa DOC
Cipro.
Flouroquinolone toxicity
Increase in QT interval, cartilage erosion, tendon rupture, GI disturbances, photosensitivity.
Flouroquinolone contraindications
pregnant and nursing women. children under 18 years of age.
Flouroquinolone resistance
changes in gyrase enzyme, decreased permeability, antibiotic modification
Metronidazole MOA
Prodrug. metabolites are taken into bacterial DNA where they form unstable molecules leading to fragmentation of the DNA. Need ferredoxin only found in anaerobes. bactericidal.
Metronidazole Spectrum
Anaerobic only. Gram positive and negative.
Pseudomembranous colitis (C-Diff) DOC
Metronidazole
Metronidazole route
oral, IV or topical.
Metronidazole toxicity
CNS with prolonged use, GI, Superinfections, metallic taste.
Exclusive UTI Drugs (2)
nitrofurantoin (Furadantin) and methenamine
Nitrofurantoin MOA
Prodrug reduced in bacteria to a metabolite that can attack and damage DNA and the ribosome. Bactericidal in the urine due to low pH.
Nitrofurantoin Spectrum
Gram positive and negative. given orally.
Nitrofurantoin toxicity
hemolytic anemia (G6PD deficiency), GI, hepatocellular damage, interstitial pulmonary fibrosis. Turns urine brown.
Nitrofurantoin contraindications
late pregnancy, less than 1 month old, low creatine clearance.
Methenamine MOA
prodrug that decomposes to formaldehye and ammonia in the urine and kills bacteria. Need low pH of the urine.
Methenamine spectrum
Gram negative with some gram positive activity.
Methenamine contraindications
hepatic and renal insufficiency.
Sulfonamides MOA
Inhibit folate metabolism by competing with PABA to prevent the reduction of DHF to THF (folic acid). Prevents purine production and inhibits DNA synthesis.
Sulfonamides spectrum
Gram positive and negative. Bacteriostatic.
TMP-SMX (Bactrim)
Sulfonamide. Made of sulfamethoxazole (inhibits PABA) and trimethoprim (inhibits dihydrofolate reductase). Oral/IV.
UTI DOC
TMP-SMX (Bactrim)
Prophylaxis for pneumocystis jiroveci infections
TMP-SMX (Bactrim)
Sulfamethoxazole (gantanol)
Sulfonamide. Oral. Slow excretion with high urine concentration.
Sulfasalazine (azulfidine)
Sulfonamide. Oral. GI action, prodrug. Used to treat ulcerative colitis and RA.
Silver sulfazalazine
Sulfonamide. topical burn treatment.
Sulfonamides Elimination
metabolized in the liver, excreted by the kidney.
Sulfonamides Contraindications
late pregnancy, nursing or premature/jaundiced infants. Any infants less than 2 months old.
Sulfonamides resistance
increased PABA production, efflux pumps, decreased permeability, alternative metabolism (plasmids).
Sulfonamides toxicity
SJS, kernicterus (compete with bili binding), aplastic anemia (G6PD), hematopoietic toxicity, kidney/liver damage, photosensitivity, common drug allergy.
Daptomycin (cubicin) MOA
Lipoprotein antibiotics that forms transmembrane channels that lead to rapid depolarization causing cell death. Bactericidal.
Daptomycin (cubicin) spectrum
Bactericidal against Gram positives (MRSA and MSSA)
Daptomycin (cubicin)
IV. Empiric therapy in patients with a serious gram positive infection. Used as an alternative to vancomycin.
Mupirocin (bactroban) MOA
reversibly binds to tRNA synthetase so it can’t make isoleucine tRNA. Inhibits protein and RNA synthesis. Produced by pseudomonas fluorescens.
Mupirocin (bactroban) spectrum
Gram positive and negative. Usually bacteriostatic but can be bactericidal at high concentrations.
Mupirocin (bactroban)
topical or intranasal application for infections of MRSA. Also used for impetigo (S. aureus and Streptococcus pyogenes).
Polypeptide antibiotics MOA
lipid a endotoxin (gram negative cell membranes only).
Polypeptide antibiotics spectrum
gram negative bacilli
Polymyxin B (aerosporin)
Polypeptide antibiotics. topical
Colistin (polymyxin E)
Polypeptide antibiotics. topical.
Polypeptide antibiotics uses
Usually used in combination with neomycin and bacitracin as topical ointment. Also active against pseudomonas in the eye.