Antimicrobials Flashcards
_______ have a bacteriostatic action, but are bactericidal in nature
Aminoglycosides
Antimicrobial: Favorable distribution into bone
Clindamycin
Antimicrobial: Favorable distribution into CSF
Ceftriaxone, Chloramphenicol, Metronidazole
Antimicrobial: Favorable distribution into gingival fluid
Tetracyclines
Antimicrobial: Favorable distribution into lungs
Macrolides
Antimicrobial: Favorable distribution into sebum
Tetracyclines
Antimicrobial: Favorable distribution into urine/kidneys
Aminoglycosides, Fluoroquinolones, Nitrofurantoin
Antimicrobial: Unfavorable distribution into a fetus
Aminoglycosides, Chloramphenicol, Tetracyclines, Fluoroquinolones, Metronidazole
Antimicrobial: Unfavorable distribution into bone
Tetracyclines
Antimicrobial: Unfavorable distribution into breast milk
Macrolides, Clindamycin
Antimicrobial: Unfavorable distribution into kidneys
Aminoglycosides
Antimicrobial: Unfavorable distribution into teeth
Tetracyclines
Bind and decrease absorption of cations, especially calcium
Fluoroquinolones, Tetracyclines
Examples of Fluoroquinolones (3)
Ciprofloxacin, Levofloxacin, Moxifloxacin
In bactericidal mechanisms MIC __ MBC
=
In bacteriostatic mechanisms MIC __ MBC
«
Indications for bactericidal therapy (3)
Meningitis, Endocarditis, Suppressed/Deficient Immune System
Inhibitors of P450
Fluoroquinolones, Erythromycin, Clarithromycin
IV only antimicrobials (5)
Piperacillin/Tazobactam, Vancomycin, Ceftriaxone, Carbapenems, Aminoglycosides
Lowest concentration of antibiotic that kills 99.9% of the original inoculum
Minimum Bactericidal Concentration (MBC)
Lowest concentration of antibiotic that prevents visible bacterial growth
Minimum Inhibitory Concentration (MIC)
Mechanism of Action: Beta-lactamase inhibitor
Clavulanate, Tazobactam
Mechanism of Action: Decrease DNA function
Fluoroquinolones, Nitrofurantoin, Metronidazole
Mechanism of Action: Decrease protein synthesis
Macrolides, Tetracyclines, Clindamycin, Chloramphenicol, Aminoglycosides
Mechanism of Action: Inhibit Cell Wall Synthesis- Stage 2
Vancomycin
Mechanism of Action: Inhibit Cell Wall Synthesis- Stage 3 (Anti-pseudomonal)
Piperacillin/Tazobactam
Mechanism of Action: Inhibit Cell Wall Synthesis- Stage 3 (Extended Spectrum)
Amoxicillin +/- Clavulanate, Ampicillin
Mechanism of Action: Inhibit Cell Wall Synthesis- Stage 3 (penicillinase-resistant)
Dicloxacillin
Mechanism of Action: Inhibit Cell Wall Synthesis- Stage 3 (prototype, acid-stable)
Penicillin G, Penicillin V
Only obtain fluid cultures from drains or catheters if _____.
they are newly placed
Protected Locations/Infections that complicate antibiotic treatment (6)
Meningitis, Bone, Endocarditis, Intracellular, Abscesses, Foreign bodies
Side Effects: Antabuse-like effect: abdominal distress, headache, and vomiting with consumption of alcohol due to inhibition of aldehyde dehydrogenase
Metronidazole
Side Effects: can intensify oral anticoagulants (Ex. warfarin)
Cephalosporins
Side Effects: Drug-drug interactions with antacids and iron supplemens
Tetracyclines
Side Effects: encephalopathy or convulsions at high dose
Penicillin
Side Effects: increased risk of tendon rupture and arthropathies
Fluoroquinolones
Side Effects: ototoxicity, nephrotoxicity, and infusion-related symptoms
Vancomycin
Side Effects: pseudomembranous colitis
Clindamycin
Side Effects: QT interval prolongation
Macrolides, Fluoroquinolones (rare)
Side Effects: supferinfection
Extended spectrum penicllins, cephalosporins, fluoroquinolones, Nitrofurantoin (candida), tetracyclines (fungal)
Side Effects: Vestibulocochlear Nerve Damage (irreversible) and nephrotoxicity
Aminoglycosides
Side Effects:drug-drug interactions: inhibits metabolism of theophylline (earlier generations), antacids reduce oral absorption
Fluoroquinolones
Spectrum: can be treated only with ceftriaxone of the cephalosporins
Neisseria gonorrhoeae
Spectrum: Can be used to treat Bacteroides fragilis
Amoxicillin +/- Clavulanate, Piperacillin/Tazobactam, Carbapenems, Clindamycin, Nitrofurantoin
Spectrum: Can be used to treat Chlamydia and Mycoplasma
Macrolides, Tetracyclines, and Fluoroquinolones
Spectrum: can be used to treat Klebsiella with KPC or NDM-1
Fluoroquinolones and Aminoglycosides
Spectrum: can be used to treat Neisseria Gonorrhoeae
Ceftriaxone, Macrolides, Tetracyclines
Spectrum: Can be used to treat Pseudomonas
Piperacillin/Tazobactam, 4th/5th Cephalosporins, Carbapenems (exc. Ertapenem), Aminoglycosides, Fluoroquinolones (Cipro, Levo)
Spectrum: Can treat Clostridium difficile
Metronidazole and Vancomycin (oral only)
Spectrum: Can treat E coli, except for when E coli has TEM-1, ESBL, or SHV-1
Amoxicillin, Ampicillin
Spectrum: Effective for E coli and E coli with TEM-1, but not for E coli with ESBL
Cephalosporins
Spectrum: Good coverage of gram-negative, poor coverage of gram-positive
Aminoglycosides
Spectrum: only effective for anaerobes (Clostridium and Bacteroides)
Metronidazole
Spectrum: only used for isolates recovered from urine
Nitrofurantoin
When to obtain specimens and from where
Before start of therapy; tissues or fluids, especially deeper specimens
When to use empiric antibiotic treatment.
Life threatening conditions; outpatient setting