Anti-Bacterials

Question 1

Name the classes of B lactams

Answer 1

penicillins, cepalosporins, carbapenemas, aztreonam

Question 2

natural penicillin

Answer 2

G–narrow spectrum, gram positive, given IV

V–acid stable, unpredictable absorption, orally given

Question 3

beta lactamase reistant penicillins

Answer 3

penicillinase resistant
“not affected”
nafcillin, oxacillin, cloaxacillin, dicloxacillin, methicillin

Question 4

extended spectrum penicillins

Answer 4

amoxicillin
ampicillin–rash in patients with mono
ticarcillin, piperacillin, mezlocillin, carbenicillin

Question 5

penicillinase inhibitors

Answer 5

inhibit beta lactamase

sulbactam & clavulanic acid

Question 6

how do beta lactams work

Answer 6

bind penicillin binding protein and inhibit crosslinking

Question 7

cephalosporins

Answer 7

each generation has more gram -, broader spectrum, greater resistance to b-lactamases

1–cephalexin & cefazolin
2–cefactor, cefuroxime, cephamycins (cefoxitin & cefotetan)

SE: allergic rxn

Question 8

carbapenems

Answer 8

small penicillinase resistant beta lactams
enter the CNS more readily

“imminent meteor”
imipenem–gram +, nephrotoxic product so always given with cilastatin
merorpenem–gram -

Question 9

monobactam–aztreonam

Answer 9

not affected by beta-lactamases
useful versus aerobic gram -
no allergic rxn
SE: seizures

Question 10

Name the non-beta lactam cell wall inhibitors

Answer 10

vancomycin, televancin, dalbavancin, bacitracin, fosfomycin, cycloserine

Question 11

vancomycin

Answer 11

binds dialanine residues-prevents crosslinking
alternative to penicillin for staph
SE: ototoxcitiy and “red man”–rapid IV causes histamine and flushing, rash, itching
Resistance: target is changed to lactic acid

Question 12

bacitracin

Answer 12

inhibits recycling of bactophenol carrier or gram +

only topically used

Question 13

fosfomycin

Answer 13

blocks synthesis of n -actylmuramic acid
treats UTI
SE: diarrhea

Question 14

cycloserine

Answer 14

inhibits enzyme
used aginast mycobacterium tuberculosum
SE: CNS, sedation

Question 15

What agents inhibit bacterial protein synthesis

Answer 15

macrolides–erythromycin
aminoglycosides–streptomycin
tetracyclines–tetracycline

Question 16

macrolides

Answer 16

macROlides–eryTHROmycin–inhibit transLOcation
activates motillin

clarithromycin–acid stable, against helicobacter pylori
azithromycin–macrolide of choice
telithromycin–less resistance because it isn’t transported as readily, SEVERE liver toxicity

Question 17

aminoglycosides

Answer 17

streptomycin
irreversibly bind 30S subunit, inhibit tRNA binding
SE: very potent, odotoxic, nephrotoxic (MOST COMMON),fetal damage
only work on aerobic gram -

Question 18

tetracyclines

Answer 18

reversibly bind 30S, bacteriostatic
deposited in calcium storage sites–stained teeth and altered bone formation
don’t use after expiration date–renal and hepatic toxicity

doxycycline, minocycline, tigecycline

Question 19

chloramphenicol

Answer 19

inhibits enzyme peptidyl transferase

SE: aplastic anemia, grey baby syndrome

Question 20

lincosamides

Answer 20

clindamycin & lincomycin
inhibits translocation of ribosome
SE: severe superinfection with C. difficile

Question 21

streptogramins

Answer 21

quinupristin & dalfopristin
always used together
inhibit A and P sites

Question 22

oxazolidinones–linezolid

Answer 22

inhibits binding of f-methionye tRNA to P site

SE: anemia, pseudomembranous colitis

Question 23

Ab that do not act at cell wall or on protein synth

Answer 23

daptomycin
lipopeptide
disrupts bacterial cell membrane & forms pores 
SE: eosinophilic pneumonia
aerobic gram + only

fidaxomycin–orally, targets C. difficile by inhibiting C. diff RNA poly

Question 24

ciprofloxacin

Answer 24

inhibits topoisomerase (only bacterial)
SE: damage cartilage, tendonitis, tendon rupture, phototoxicity

Question 25

anti-metabolites

Answer 25

sulfonamides & sulfisoxazole
reversibly inhibits enzyme
SE: stevus johnsons
treats UTI

Question 26

trimethoprim

Answer 26

inhibits dihydrofolate reductase
SE: megaloblastic anemia
treats UTI

Question 27

metronidazole

Answer 27

used for protozoal infections

Question 28

nitrofurantoin

Answer 28

used for UTI

SE: cough, brown urine

Question 29

polymixin B

Answer 29

causes increased membrane permeability

topically

Question 30

gramicidin

Answer 30

form pores in bacterial membrane
systemic toxicity for all organs
used topically

Question 31

what treats leprocy

Answer 31

dapson