Antibiotics Flashcards
Protein synthesis inhibitors
MALT - P
Macrolides (50s)
Aminoglycosides (30s)
Lincosamides (50s)
Tetracyclines (30s)
Phenicols (50s)
Fluoroquinolones MOA
Inhibit DNA/nucleic acid synthesis
Sulfonamides MOA
Inhibit folic acid synthesis
Metronidazole MOA
Inhibits nucleic acid/DNA synthesis
Cell wall synthesis inhibitors
Cephalosporins
Penicillins
Carbapenems
Glycopeptides
Polymixins (target cell membrane function)
Bacteriostatic drugs
SMLT-P
Sulfonamides
Macrolides
Lincosamides
Tetracyclines
Phenicols
Bacteriocidal drugs
Aminoglycosides
Polymixins
Metronidazole
Glycopeptides
Fluoroquinolones
Cephalosporins
Carbapenems
Penicillins
TMS
Time dependent drugs
Penicillins
Carbapenems
Cephalosporins
Glycopeptides
Lincosamides
Phenicols
Macrolides
Tetracyclines
Polymixins
Sulfonamides
Concentration dependent drugs
FAM:
Fluoroquinolones
Aminoglycosides
Metronidazole
Aminoglycosides: coverage and drug examples
Gram - and pseudomonas
Streptomycin, gentamicin, amikacin, neomycin
Cephalosporins: 1st gen coverage and drug examples
G+»_space; G- and moderate anaerobes
Cefazolin, cephalexin
Cephalosporins: 2nd gen coverage and drug examples
G+ > G- and good for anaerobes
Cefoxitin (great for anaerobes)
Cephalosporins: 3rd gen coverage and drug examples
G - > G+ (except not cocci), excellent for anaerobes
Cefovecin, cefpodoxime
Tetracyclines coverage
G+, poor for G - /anaerobes
Penicillins: types and their coverage
Naturals: G+ and anaerobes
Aminopenicillins: G +/- and anaerobes
Anti-pseudomonal: pseudomonas
Anti-staphylococcal: G+ and anaerobes. Not MRSA
B-lactamase inhibitors: G +/- and anaerobes
Sulfonamides coverage
Gram +/- and anaerobes and Nocardia
Fluoroquinolones coverage
G+/- but poor for anaerobes
Macrolides: coverage and drug examples
Gram + and anaerobes
Azithromycin, tylosin, erythromycin (has some G- coverage)
Carbapenems coverage
Gram +/- and anaerobes
Widest coverage
Lincosamides: coverage and drug examples
G+ and anaerobes
Clindamycin, lincosamycin
Glycopeptides: coverage and drug examples
Gram + and anaerobes
Vancomycin
Chloramphenicol coverage
Anaerobes > G+ > G-
Resistance in Pseudomonas
Metronidazole coverage
Anaerobes
Antiprotozoal infections
Polymixin coverage
Gram - including Pseudomonas
Indications for natural penicillins
Clostridial disease, listeriosis, actinomycoses, anaerobic infections
Aminopenicillin indications
Cat abscesses, uncomplicated UTI. NOT FOR SURGICAL PROPHYLAXIS
Clavamox indications
Everything other than CNS, prostate, and bronchus
Penicillin side effects
Low toxicity
Hypersensitivity and GI
Indications for Carbapenems
Highly resistant infections, especially MDR G- infections
Indications for cephalosporins
Susceptible staphylococcus, UTIs, surgical prophylaxis, skin infections, osteomyelitis, discospondylitis
3rd gen reserved for G- and anaerobes, especially enterobacteria
Carbapenem side effects
GI, CNS, renal failure, hypersensitivity and phlebitis
Cephalosporins side effects
GI and rare hypersensitivity reactions
Fluoroquinolone indications
90-100% of respiratory, intestinal, urinary and skin infections, osteomyelitis, septic arthritis
Great for deep-seated infections and IC pathogens
Fluoroquinolone side effects
GI, cartilage deformities in growing dogs, neurologic abnormalities (seizures when combined with NSAIDs), and ocular disease in cats (retinal degeneration, blindness)
Glycopeptides (vancomycin) indications
IV MDR staph or enterococcus infections or PO for C. difficile
Glycopeptides side effects
Nephrotoxicity, ototoxicity, arrest, hypotension
Lincosamide indications
Penetrating biofilm with dental disease, strep/staph and anaerobic infections, neutralizing endotoxin, and chronic rhinitis
Lincosamides side effects
GI
NOT FOR HORSES
Chloramphenicol indications
Chronic resp inf, brain inf, intraocular inf, dermatitis, UTI (achieves high conc in urine), salmonella/bacteroides
Chloramphenicol side effects
Immunodeficiency, leukemia, aplastic anemia (dose dep or idiosyncratic)
Do not vaccinate while administering
Avoid cats with CKD
Macrolides indications
Bronchopneumonia, enteritis, UTI, septic arthritis, mastitis, dermatitis
Babesia gibsoni
Tylosin: chronic colitis, feline URI, SIBO
Mycoplasma
Macrolides side effects
Vomiting, possible liver issues, pro-motility at low doses
Metronidazole indications
Anaerobic infections (Bacteroides, Campylobacter, Corynebacterium, Clostridium)
IBD
SIBO
Hepatic encephalopathy
Metronidazole side effects
Neurologic disorders, lethargy, weakness, neutropenias, hepatotoxicity, hematuria, GI
Cats: GI, hepatotoxicity, CNS toxicity, teratogenic
Tetracyclines indications
Atypical bacteria (Rickettsia, Borrelia, Chlamydophila, Mycoplasma)
Bronchopneumonia, enteritis, mastitis, dermatitis, tick-borne, MRSA (doxy)
Tetracyclines side effects
Esophageal stricture
Hepatotoxicity, hypersensitivity, anemia, GI, hypotension, negative effects on growing teeth and bone, can impair rapidly dividing cells (80s ribosomal subunit)
Polymixin indications
Topically for skin inf, Ophtho ointment, endotoxic shock
Polymixin side effects
SERIOUS NEPHROTOXICITY, CNS toxicity, histamine release
Aminoglycosides indications
Poor tissue penetration, not really abs in gut
G- inf resistant to B lactams
Overwhelming sepsis
Topical for skin/eye/ear inf
Neomycin: hepatic encephalopathy, GI bacteria
Streptomycin: leptospirosis
Aminoglycosides side effects
Nephrotoxic (proximal tubule damage, usually reversible), neurotoxic (auditory and vestibular ototoxicity - deafness not reversible)
Neuromuscular blockade and cardiac effects
Sulfa drug indications
Osteomyelitis, Prostatitis, pneumonia, tracheobronchitis, staph pyoderma, UTIs
Not good for chronic inf with high bacterial load
Sulfa drug side effects
Type III hypersensitivity reactions (IMPA, etc)
Doberman and other black/tan breeds predisposed to hypersensitivity
Lacrimal gland toxicity - KCS
Idiosyncratic hepatic necrosis
Aplastic anemia
Thyroid
Abx that concentrate in bile
Rifampin, doxycycline, erythromycin, clindamycin
Antibiotics that penetrate the prostate
Fluoroquinolones, TMS, erythromycin, clindamycin
Also chloramphenicol and doxycycline
Antibiotics that cross the BBB
Pradofloxacin, rifampin, metronidazole, TMS,
Doxycycline, chloramphenicol
+/- cephalosporins and vancomycin
What antibiotic has inherent resistance to G+ bacteria?
Polymixin
What antibiotics have inherent resistance with anaerobes?
Aminoglycosides +/- Fluoroquinolones
Aerobes are inherently resistant to what antibiotic?
Metronidazole
What is MIC
Minimum inhibitory concentration, tells bacteriostatic activity
What is MBC
Minimum bactericidal concentration, tells bactericidal activity
A drug is concentration dependent if
Cmax is > than MIC by 10-12x
Time dependent drugs depend on…
The time that the plasma drug concentration (PDC) is above the MIC
PDC should be 2-4x the MIC for much of the dosing interval
Antagonistic antibiotics
Robosomal inhibitors and beta lactams
Beta lactams rely on protein synthesis and growth of the organism
(Except chloramphenicol and ampicillin are synergistic for staphylococcus)
Aminoglycosides are synergistic with
Beta-lactams
Bacteria that form biofilms
Staphylococcus, Pseudomonas, Klebsiella, Actinobacillus, Acinetobacter
