Pharm 43

Front 1

penicillin basic structure

Back 1

thiazolidine ring attached to a B-lactam ring that carries a secondary amino group

Front 2

what are penicillins most affective against

Back 2

gram-pos; gram-neg cocci; non-B-lactamase producing anaerobes

Front 3

what are antistaphlococcal penicillins most affective against

Back 3

resistant to staph B lactamases; active against staph and strep

Front 4

MIC

Back 4

minimum inhibitory unit

Front 5

what is the fxn of PBP

Back 5

removes terminal alanine in process of forming a cross-link with a nearby peptide

Front 6

where do B-lactam antibiotics bind

Back 6

to active site of PBPs

Front 7

most common mechanism of resistance to penicillins

Back 7

B-lactamase production

Front 8

methicillin resistance

Back 8

altered target PBPs

Front 9

when does resistance to impaired penetration occur with penicillins

Back 9

in gram-neg species

Front 10

excretion of penicillin

Back 10

rapidly by kidneys

Front 11

what penicillins are excreted by biliary excretion

Back 11

nafcillin; dicloxacillin and cloxacillin are kidney and biliary

Front 12

probenecid

Back 12

impairs renal tubular secretion of weak acids (like B-lactams) and can raise blood levels of these drugs

Front 13

what is generally used in place of the oral penicillin V for minor infections

Back 13

amoxicillin

Front 14

extended spectrum penicillin benefit

Back 14

greater activity than penicillin against gram-neg; enhanced ability to penetrate outer membrane

Front 15

penicillin hypersensitivity

Back 15

all are cross-reacting and cross-sensitizing

Front 16

skin rashes from ampicillin and amoxicillin

Back 16

not allergic in nature and frequently occur when prescribed inappropriately for a viral illness

Front 17

methicillin side effect

Back 17

interstitial nephritis (no longer used for this reason)

Front 18

first-generation cephalosporins action and specs

Back 18

lots of c names; active against gram-positive cocci; kidney excretion

Front 19

only first-generation cephalosporins still in general use

Back 19

cefazolin - used in surgical prophylaxis

Front 20

second generation cephalosporins

Back 20

lots more c names; large variation in activity, toxicity, etc; in general also have gram-neg coverage; renal clearance

Front 21

main uses of second generation cephalosporins

Back 21

active against H influenzae and moraxella catarrhalis - thus used to treat sinusitis, otitis, and lower resp infections

Front 22

third generation cephalosporins

Back 22

expanded gram-neg coverage, some cross blood-brain barrier; most excreted by kidney

Front 23

cefoperazone and ceftriaxone - third generation cephalosporins are excreted via

Back 23

biliary tract

Front 24

fourth generation cephalosporins

Back 24

more resistant to hydrolysis by chromosomal B lactamases; cleared by kidneys; activity against strep resistant to penicillins; enterobacter infection usefullness

Front 25

example of 4th generation cephalosporins

Back 25

cefepime

Front 26

cross-reactivity of hypersensitivity rxns btwn penicillins and cephalosporins

Back 26

5-10%

Front 27

side effect of cephalosporins with methylthiotetrazole group

Back 27

hypoprothrombinemia and bleeding disorders; administer vit K1 can prevent; also have disulfiram like rxns (avoid alcohol consumption)

Front 28

monobactams

Back 28

monocyclic B-lactam ring; aerobic gram-neg rods (pseudomonas)

Front 29

only available monobactam in US and uses

Back 29

azetreonam - penetrates CSF; renal excretion; good in penicillin allergic patients

Front 30

Beta-Lactamase inhibitors activity

Back 30

Ambler class - plasmid-encoded

Front 31

carbapenems

Back 31

end in -penem; resistant to most B lactamases (not metallo-B-lactamases); enter CSF well; renal clearance

Front 32

cilastatin

Back 32

inhibitor of renal dehydropeptidase - extends life of carbapenems

Front 33

adverse effects of carbapenems

Back 33

nausea, vomiting, diarrhea, skin rashes

Front 34

imipenem adverse rxns

Back 34

seizures in renal failure patients

Front 35

vancomycin activity

Back 35

gram-pos; binds D-ala D-ala terminus of nascent peptidoglycan pentapeptide - prevents elongation and cross-linking; renal excretion

Front 36

resistance to vancomycin

Back 36

D-ala replaced by D-lactate

Front 37

adverse rxn to vancomycin

Back 37

10% cases - minor; red neck syndrome - release of histamine

Front 38

daptomycin specs

Back 38

MOA not understood; bind cell membrane via Ca2+ dependent insertion of lipid tail; renal clearance

Front 39

why shouldn't daptomycin be used for pneumonia

Back 39

pulmonary surfactant antogonizes the drug

Front 40

fosfomycin mechanism of action

Back 40

inhibits cytoplasmic enzyme enolpyruvate transferase by covalently binding to systeine residue of active site and blocking addition of phosphoenolpyruvate to UDP-N-acetylglucosamine

Front 41

fosfomycin action

Back 41

gram pos and neg; kidney excretion; safe in pregnancy

Front 42

bacitracin specs

Back 42

cyclic peptide mixture; gram-pos; ointment use

Front 43

bacitracin mechanism

Back 43

interferes with dephosphorylation in cycling lipid carrier that transfers peptidoglycan sununits to the growing cell wall

Front 44

cycloserine specs

Back 44

gram pos and neg; TB 2nd line agent; renal excreation

Front 45

cycloserine mechanism

Back 45

analog of D-alanine and inhibits incorporation by inhibiting alanine racemase

Front 46

cycloserine toxicity

Back 46

dose-related CNS - headaches, tremors, acute psychosis, convulsions