Exam 1 - Cushman (Lecture 4) Flashcards
aminoglycosides and tetracyclines are the only drugs that bind to the ___ subunit, the rest bind to ___
30S, 50S
clindamycin clinical uses
IV: bone infections
topical: severe acne
clindamycin effective against gram (-/+)
both, aerobic gram (+), anaerobic gram (-)
clindamycin may cause a potentially lethal reaction called ______ ______
pseudomembranous colitis, may lead to overgrowth of C. diff. which can cause toxic megacolon and diarrhea
when pseudomembranous colitis is recognized (caused by C. diff.), what agent should be used to treat?
metronidazole or vancomycin
why should you avoid drinking milk and taking OTCs with metal ions such as Ca, Al, Cu, Mg with tetracyclines?
chelation may occur, inactivating the tetracycline
Can you use tetracyclines in pregnancy?
up to the 4th month of pregnancy
What else besides chelation may happen to tetracyclines?
epimerization
dehydration
cleavage in base
Chloramphenicol is used more in third world countries. Why?
It is inexpensive. It is also effective in a broad spectrum, however, it comes with risks.
3 resistance mechanisms to chloramphenicol
- reduced membrane permeability
- mutation of the 50S ribosomal subunit
- elaboration of chloramphenicol acetyltransferase
chloramphenicol and ______ makes glucurodine which is ineffective
UDPGA
most serious tox. of chloramphenicol
aplastic anemia (rare, generally fatal)
-occurs weeks-months after treatment has been stopped
common side effect of chloramphenicol
bone marrow suppression
quinolone examples
oxolinic acid (1st)
nalidixic acid (1st)
ciprofloxacin (2nd)
levofloxacin (3rd)
moxifloxacin (4th)
ozenoxacin (New)
Delafloxacin (New)
Ozenoxacin use
topically to treat IMPETIGO due to Staph. aureus or Strep. pyogenes
Delafloxacin uses
oral or IV for treatment of skin infections caused by wide variety of gram (-) and (+) bacteria, including MRSA
In gram (-) bacteria, quinolones bind to the ____ ____ ____, blocking its activity. This stops the DNA from _____
DNA gyrase enzyme, replicating
are quinolones bactericidal or bacteriostatic?
bactericidal
In gram (+) bacteria, quinolones bind to the ____ ____ ____, blocking its activity. This stops the DNA from _________
Topoisomerase IV enzyme, separating
-picture with red lines for drug from lecture
increased fluoroquinolone resistance rates are correlated with _____ use
increased
fluoroquinolones have (good/bad) oral bioavailability and are _____ distributed
good, widely
Gatifloxacin has been associated with what unique SE
hyper or hypoglycemia in diabetes patients
