Antibacterials Flashcards
What are indicators of an infection being bacterial? (2+ are required for it to be bacterial)
Absence of a cough 3-14yo patient Anterior cervical lymphadenopathy Fever Tonsillar erythema or exudates
What are some examples of beta-lactams?
Penicillins
Carbapenems
Aztreonam
What do beta-lactams bind to?
Penicillin Binding Protein…transpeptidase required in cell wall synthesis
What other drug works on gram+ bacteria by preventing cell wall synthesis?
Vancomycin
What does vancomycin bind to?
D-Ala-D-Ala–prevents synthesis of NAM/NAG-peptides
What should be given if a person goes into anaphylaxis?
Epinephrine…think about the effects on the different receptors
What are the macrolides? Ketolides?
Erythromycin
Azithromycin, Clarithromycin
How do macrolides/ketolides kill bacteria?
Inhibit translocation of ribosome…binds to 23S rRNA of 50S subunit
What kind of bacteria do macrolides/ketolides kill?
Broad spectrum
How do bacteria gain resistance against macrolides/ketolides?
Methylation of 23S rRNA, Efflux
What are some side effects to macrolides/ketolides?
GI discomfort Prolonged QT interval Hepatic failure (inhibits CYP3A4)
What other side effect is associated with clarithromycin?
Miscarriages
What are the fluoroquinolones?
Gemifloxacin
Levolfloxacin
Moxifloxacin
the FLOXACINs
How do fluoroquinolones work?
Bind to Topo II and IV
Bactericidal
What do fluoroquinolones work against?
Broad spectrum… including mycoplasma
What are some forms of resistance to fluoroquinolones?
Active efflux of the drug
Mutations in topos
What are the side effects of fluoroquinolones?
GI discomfort
Tendinopathies
Who shouldn’t be given fluorquinolones?
Pregnant or lactating women
Children
What is the mechanism of tetracyclines (doxycycline)?
Bind 30S of rRNA…prevents binding to A site
Bacteriostatic
What causes the resistance to doxycycline?
Reduced uptake
Increased efflux
Widespread
What are the adverse effects of tetracyclines?
Photosensitivity
Discoloration of teeth
Inhibits bone growth
When should doxycycline be avoided in?
Pregnant women
Children
What limits oral absorption of tetracyclines and fluroquinolones?
Cations…chelating
What do polymyxin E/colistin fight against?
MDR gram-
How do poymyxin E/colistin kill MDR gram- bacteria?
Bind phosphatidylethanolamine –> holes in membrane
Should colistin be used often?
No…nephrotoxicity–it should be used as a last resort
Is resistance to polymyxin E likely?
No
