Antibiotics 4 Flashcards

Terms Definitions
Trimethoprim/Sulfmethoxazole niche
Ketolide drug
Time-Dependent Killing
Vibra-tabs (tetracycline)
Nizoral (antifungal)
Gram +
-peptidoglycan-PBPs-beta lactamases
Azteonamresistant to B-lactamaseseffective against Gram- (esp Enterobact.) but not Gram+
30S drugs
AG-multiple sites
tetracyclines-A window
tigecycline-A window
Streptococcus category
Gram-positive cocci
RNA Polymerase Abx
Myambutol (TB prophylactic)
IritisuveitisICP up
Foscarnet- therapeutic
gram -, obligate anaerobes
How is Vancomycin cleared?
blocks dephosphorylation of bactoprenol;; Kill Gram +; administer topically
How is penicillin eliminated?
50S drugs
AG-multiple sites
Chloramphenicol-A window
Clindamycin-A window
Macrolides-P window
Tlithromycin/ Q-D/Linezolid-23S
H. Flu
M. Cat

DO NOT cover most enterobacteriacae
Penicillinase resistant, penicillinase producing gm+ orgs
Only 4th gen Cephalosporin?
Fortaz (3rd generation cephalosporin)
Don't give quinolones to....
first to break through vancomycin
Extended spectrum antibiotic, stable to penicillinase. Orally administered.
DOC for bite wounds.
inhibitors of 50S ribosomal subunit
similar action and resitance as macrolides
Clindamycin used to treat serious gram- infections --> pseudomembranous enterocolitis associated with overgrowth of C. difficile
Clindamycin; Binds 50S subunit, inhibits peptide bond formation; Useful against VREF, MRSA and MSSA
characterize bacteroides(gram stain, shape, metabolism)
Gram-RodObligate anaerobe
phototoxicity- even days after stopping

QT interval prolongation
Ethambutol MOA
inhibits mycobacterial arabinosyl transferases->involved in polymerization of arabinogalactan

bacteriostatic-inhibits cell wall synthesis
sulfonamide metabolism
-not extensively metabolized
-mainly by acetylation of primary amino group on aromatic ring
sulfonamide MOA
inhibition of dihydropteroate synthetase

para-aminophenyl-sulfonamide moiety resembles PABA --> bacteria can't make thymidylate (T) --> can't make dihydrofolic acid (DHFA) --> bacteriostatic
What metabolizes the Macrolides?
The liver
T/F Third Generation Cephalosporin Ceftriaxone: (Rocephin) is given by IV and IM, has a long half life, is a once a day dosing and it easily passes meninges and diffused into CSF to treat CNS infections.
Ampicillin, Ampicillin/sulbactam
Aminopenicillin (Extended Spectrum), same gm+ as pen G, some gm- (E. coli, H. flu)
Aminoglycoside dosing [3]
-Extended (Hartford Nomogram)
Inhibit protein synthesis; inhibits transpeptidation prevents protein production by the bacterial cell w/o affecting the human cell t
moa of cephs
same as pens
Adverse effects of amantadine:
CNS toxicity
most bacteria are...
facultative anaerobes or microaerophilic bacteria (aerotolerant anaerobes)
breakdown product of skeletal muscle -eliminated through the kidney-if creatinine is not being eliminated as if normal than serum creatinine goes up=way to tell if abnormal kidney function
some Gram -
Are the macrolides bacteriastatic or cidal?
azithromycin spectrum
strptococci, staph auresu, h.flu, atipical bacteria including mycoplasma, chlamydiae, legionella.
4th generation cephalosporins
Cefepimebroadest spectrum against Gram+/-resistant to B-lactamases
Which class of antibiotics can produce tooth discoloration and inhibit long bone growth in young animals?
MOA of streptogramins
Bind 50S ribosomal subunit
what is used to tx SIADH
Moxifloxacin coverage
most bacteria--little less effect. than 2/3rd gen in enterobacteriacae
sulfonamide hypersensitivity reactions
-Steven-Johnson syndrome
-present on 9th day of tx; consequent exposure causes immediate rxn
-more common with long-acting sulfonamides
efflux mechanisms
-often seen in pseudomonas
-increased expression of P-GP (p-glycoprotein) efflux pump
T/F Third Generation Cephalosporin are Less active against Gram + organisms.
Cephalosporins-3rd gen, more gm-, less gm+, moderate against pseudomonas
Pseudomonas aeruginosa
-gram -
-Pseudomonas can become resistant to everything
Tetracycline (Protein sys. 30S) - Doxycline
What is the broadest spectrum antibiotic?
Adverse effects of linezolid...
myelosuppression, hypersensitivity, peripheral neuropathy, serotonin syndrome
no affected by the two major tetracycline resistance mechanisms (ribosomal binding site alteration, active efflux); considered bacteriostatic
What drug class may cause similar symptoms to Myesthenia Gravis?
gram neg aerobic enterobacteriaceae, true pathogens
-salmonella typhi-salmonella enteriditis-shigella dysenteriae-yersinia pestis
Agents for deep fungal infections
Amphotericin B (IV)FluconazoleKetoconazolesFlucytosineItraconazole
Which is more potent amoxicillin or ampicillin?
tx for systemic mycotic infection and fungal meningitis caused by cryptococcus and candida species
Drugs that inhibit protein synthesis
Oxazoladinones, tetracyclines, aminoglycosides, chloramphenicol, loncosamines, macrolides, Type B streptogramins, ketolides
Name 2 aminopenicillin preparations that have some G(+)/G(-) coverage and are effective against beta lactamase producing organisms
Ampicillin/sulbactam (Unasyn), Amoxacillin/Clavulanate (Augmentin)
Beta-lactamase inhibitors
Clavulanic acid, sulbactam. Use in combination with broad and extended spectrum penicillins
Pharmacokinetics of itraconazole
Orally effective; absorption increased by food; metabolized by liver enzymes; inhibits P450
metronidazole absorpt./ distrib/ elim.
well absorbed orally
great penetration->CNS
what is the major pathway of elimination for most penicillins, cephalosporins, carbapenems and aztreonam
inhibits addition of lactoyl group to UDP-NAG thus inhibits formation of UDP-NAM

single 3g dose for uncomplicated UTIs; alternative for Bactrim DS (sulfa-trim); safe for pregnancy
What combination make up Zosyn?
Piperacillin + Tazobactam
Presence of viable bacteria in the blood
ABx with poor Lung Penetration [1]
Drugs with toxic or growth inhibitory effects
4th gen cef
resists more beta lactamases
given parenterally - excellent pen into csf
nosocomial infections
Adverse effects of tetracyclines....
photosensitivity, dental staining, hepatotoxicity, vertigo
What are predisposing factor for ototoxicity of AGs?
concurrent ototoxic drugs
What antibiotic is used as first line treatment for pasteurella multocida (animal Bites)?
A blood culture that is positive for what is most likely not significant and is just a skin contaminant?
Proteus mirabilis (indole positive)
-gram neg, enteric bacilli-virulence: endotoxin, flagella produce "swarming appearance", urease prod.-some b lactamase proddisease: -UTIs-cystitis and pyelonephritis -Urolithiasis-all proteus sp. prod urease which split urea, generates ammonia, alkalinizes the urine, precipitation of magnesium and ammonium phosphate, staghorn calculi -kidney stones, only way to treat is to open up kidney and get out-proteus vulgaris, morganella morganii, providentia rettgeri, and providentia stuartii (indole neg)
how do aminoglycoside work
inhibit protein syntheis by irreversibly binding to 30s ribosomes
What is clarithromycin better against than erythromycin? (2)
haemophilus and moraxella
which cephalosporins generation is not effective against B-lactamases
none..all are effective
Name 2 examples of antibiotics which are antimetabolites
sulfonamides, trimethoprim
Uses of interferons
Antiviral: HBV, HCV; antiumor: Kaposi, CML, multiple myeloma, renal CA; Immunoregulatory: mutiple sclerosis
Nalidixic Acid uses
UTI's ONLY (drug conc. in urine)
->25% bacteria resistant to drug
CYP450 inhibitors
Clearly Cool Kens Vehicle Is Equally Quick
Chloramp, Clarithromycin, ketoconazole, valproic acid, Isoniazid, Erythromycin, Quinolones
oral 1st generation cephalosporins (3)
"Rad Alex Rox PO"
What combination make up Timentin?
Ticarcillin + Clauvulanic acid
Cephalosporins-2nd gen spectrum
same gm+, addit gm- (H. flu)
very slow growing bacteria with a waxy exterior
pen administration
oral, im Iv
after oral dose widely distributes in tissues and secretions ... except cns, prostatic fluid, and eye
What antibiotic is recommended for people in ICU or hospitalized for long time?
4th gen. cephalosporins
Empiric Treatment
What type of treatment is usually the inital first choice when you want to cover all of the bases?
clincamycin + PCN-G
What is the first line drug for necrotizing fascitis (group A streptococcal)?
Two vaccines developed for streptococcus pneumoniae
-Pneumococcal conjugate vaccine, 7 valent (7 distinct strains it will protect you against) -strictly a pediatric vaccine-Pneumococcal Polysaccharide Vaccine, 23 valent -covers 98% of disease causing strains -pneumovax 23, pneu-imune 23-for children >2 yr of age and high risk adults -does not stimulate antibody titers like 7 valent does
BROADER than normal penicillins
Gram + and Gram - (aerobes and most oral anaerobes)
S. pyogenes, S. pneumonia
H. flu
E. coli, L. monocytogenes (meningitis)
Vancomycin mechanism of action
Bactericidal. Works by inhibiting cell wall synthesis (not in the same way as beta lactams), in the transpeptidase reaction, it binds to the terminal D-Ala-D-Ala of the newly formed (nascent) peptidoglycan and prevents linkage.
Linezolid (Zyvox)
binds to the 50s subunit and inhibits formation of fmet-tRNA. Gram positive cocci (MRSA and VREF)
S. viridians is most often seen clinically as ____?
dental work-related SBE
Pharmacokinetics of penicillins
Most are eliminated via active tubular secretion. Nafcillin and oxacillin are eliminated in bile. Ampicillin undergoes enterohepatic circulation but is excreted by the kidney. Benzathine penicillin G repository form (t1/2: 2 weeks)
tx meningitis esp with CNS abscesses with?
chloramphenicol-pentrates abscess wall

-best of all penicillins against___ and ____
pseudominas aeruginosa and B.frag

GREAT for ANAEROBE coverage
What are the side effects of Sulfonamides in the GI Tract?
1-nausea, 2-vomiting,3-diarrhea, 4-pancreatitis
Modify protein synthesis / Bacteriostatic / Broad spectrum: Acne, STDs, Rocky Mountain Spotted Fever, Montazuma's Revenge, & Lyme Disease / Not given c antacids or dairy / Contraindicated in childeren & pregnant women *Except Doxycline
*Some antibiotics can be bacteriocidal or bacteriostatic depending on concentration*
Wide spectrum, Narrow spectrum
What is Quinupristin/dalfopristin used to treat?
serious or life threatening infections associated with vancomycin-resistant E. faecium bacteremia (VREF; bacteriostatic)
-gram + aerobe-MOST VIRULENT of the Staph species-most produce penicillinase (b-lactamase) mediated by plasmids (or chromosome itself)-penicillinase-resistant penicillin (methicillin) and cephalosporins are effective against this type of resistance
Staphylcoccus aureus -"aureus"=golden color on agar plates
vancomycin is particularily used for what?and what microbes
MRSA, g+ve aerobic and anaerobic
What drugs would you use against Vancomycin resistant microbes?
Quinopristin/ Dalfopristin, Linezolid -> for Vancomycin resistant organisms
What drug is common to any of the four forms of Leprosy (tuberculoid, borderline, indeterminate, lepromatous)?
Pharmacokinetics of vancomycin
Used IV and orally (not absorbed) in colitis. Enters most tissues but not CNS. Eliminated by renal filtration. Long t1/2
which FQ's for respiratory infections
3rd and 4th gen
levfloxacin or moxifloxacin-used lots in hospitals
what is the initial step in eliciting an immune response to an antibiotic
formation of antigen
What is Demeclocycline used for?
To treat SIADH, pleural and pericardial effusions
pen notarum
only nat occuring agent is pen g and pen v
Accounts for 40 million MD office visits yearly-Pathogens: -Group A streptococcus (15%) -other hemolytic streptococci -arcanobacterium hemolyticum -neisseria gonorrhea -chlamydia pneumoniae -epstein-barr virus (mononucleosis) -other
Pharyngitis-viruses cause more sore throat than bacterial
What are the uses for 1st generation cephalosporin?
gram +, staph, strep
3 big groups of drugs that are used in tx HIV
NNRTINRTIprotease inhibitors
which 2 TCN's undergo biliary elim
Doxy + Mino-->good for renal

but ALL can be used for HEPATIC failure
Where is the Macrolides excreted in?
In the Bile in high concentrations
Cephalosporins-1st gen spectrum
gm+, little gm-, no H. flu, no B. fragillis
Why don't penicillins harm the host?
They target the peptidoglycan cell wall; humans don’t have a cell wall structure.
cefazolin, ampicillin, erythromycin, or clindamycin
What is the second line drug of choice for cellulitis?
Name the most common enzyme that opens Beta-lactam rings
Transpeptidase (covalently binds to beta-lactam, so can be titrated down)
- mech?
- uses?
- interactions?
reduced by bacterial enzymes --> reactive and destroys DNA

Uncomplicated UTIs

NEVER combine with Nalidixic acid b/c they're antagonistic
-1 of the worst for causing ___
SEIZURES (imipenem is even worse)
short t1/2 (30 min) --> probenecid competes with renal secretor & prolongs penG's action
culture & sensitivity test
test to see if patient is allergic to penicillin
What type of bacteria does clindamycin treat?
anaerobes (due to the association with pseudomembranous colitis, use of clindamycin is largely restricted to anaerobic infections)
what is the major adverse reactions of chloramphenicol
reversible bone marrow depression and aplastic anemia that is FATAL and not dose-related
A 27-year-old male with a three-year history of AIDS complains ofprogressive blurring of vision for two days. Eye examination reveals evidenceof retinitis consistent with cytomegalic virus inclusion disease. Intravenoustreatment is started, and within fiv
Foscarnet...I know I know the first line is Ganciclovir but they put this as an answer becauseThe answer is d. (Hardman, p 1200. Katzung, p 830.) Nephrotoxicityand symptomatic hypocalcemia are major toxicities associated with foscarnet.Underlying renal disease, concomitant use of nephrotoxic drugs,dehydration, and rapid infusion of high doses increase the risk.
ceph's that tx meningitis (cross BBB)
"FURious OX and TAZ TRIed EPI in a TAXI"

If a pt is allergic to penicillin, what else may they be allergic to ? What is this called?
other cephlasporins and sulfa; called cross-sensitivity.
T or F clcloserine is an irreversible inhibitor of PBP
F it is reversible- penicillin is irrevrsible
85. Ampicillin and amoxicillin are in the same group of penicillins. Whichof the following statements best characterizes amoxicillin?a. It has better oral absorption than does ampicillinb. It can be used in penicillinase-producing organismsc. It is classi
85. The answer is a. (Hardman, pp 1084–1085.) Amoxicillin is classifiedas an aminopenicillin along with ampicillin. Because it is less affected thanampicillin by the presence of food, it has a superior absorption in the GItract. It is sensitive to penicillinase and has a narrow spectrum of activitytoward certain Gram-positive and Gram-negative organisms, but notPseudomonas. Because it is in the penicillin family, hypersensitivity reactionsare a possibility.
Pen G and V pts w renal failure clear drugs through
liver although at slower pace
in what form is an acidic drug found in the body when its pH<pKa
unionized; this is what happened with the original parent sulfanilamide drug because of its low solubility/high pKa
When can an allergy to antibiotics occur?
At any time of tx and up to 2 wks after therapy
fluoroquinolone example
sulfonamide elimination
ADE Bactrim
Azulfidine (sulfonamide)
Mycostatin (antifungal)
gram + aerobes
ciproflaxin, moxifloxin, gatifloxacinTargets DNA gyrase; against Gram +/- aerobes and fac. aerobes
DOC for anthrax
Levaquin (anti infective)
Active against Atypicals
Seromycin (TB retreatment)
Stevens johnson antibiotics
gram + diplococci =
non B-lactams
Vancomycin, Bacitracin, others
Name 6 enetrics (enterobactereaceae).
clindamycins distribution
GI absorbed>lincomycin
distributes into tissues, body fluid, and bone

poor CSF pen->NOT for meningitis
DOC for TB prophylaxis
True/False. In Aminoglycosides, patients must be monitored for drug level to prevent toxicitity.
Piperacillin, Piperacillin/tazobactam
Antipseudomonal Penicillin, pseudomonas
erythromycin base EC pellets
Maxipime (4th generation cephalosporin)
shigella dysenteriae
gram - enterobacteriacae rodsVirulence: -enterotoxins-Shiga A and B -endotoxins -invasion -resists stomach acid (extremely contagious)Disease: -dysentery (shigellosis)-watery diarrhea, fever, N&V, -can be fatal to sm children-Transmission: fecal/oral-exteremely contagious requiring v. sm amts of bacteria
not yet approved
isolated from natural products from Streptococcus

discovered to activate a bacterial protease (ClpP) to more efficiently degrade proteins and to degrade proteins not usually degraded by the protease
Cephalosporins 1st generation
Cephalexin, cefazolinnon-life threatening infections/prophylaxis; susceptible to lactamases from Gram-; narrow spectrum
What protozoal infection is clindamycin used for?
more S.E. for erythromycin
thrombophlebitis-IV erythrom

transient deafness-in elderly(IV)-revers. after 6-14 days
Telithromycin S.E.
POTENT 3A4 inhibitor

visual difficulties

hepatotoxic(BLACK box)

inhibits presynaptic release of ACh (avoid in pt's with myasthenia gravis)
carbenicillin prodrug
-carbenicillin indanyl sodium
-the only PO formulation amongst PM CAT penicillins
True/False. Are Carbapenem highly resistant to beta-lactamases?
T/F First Generation Cephalosporin Cephalexin: (Keflex and Keftab) are given PO and used for surgical prophylaxis, URIs, otitis media.
T/F Second Generation Cephalosporin Cefoxitin: (Mefoxin) are given IV and IM and are used prophylactically for abdominal or colorectal surgeries; also kills anaerobes.
Fluoroquinolones, excellent gm- (H. flu), decent gm+, excellent shigella & salmonella
Anerobic Organisms [3]
-Clostridium sp.
-Bacteroides fragilis
infectious disease caused by fungi
beta lactams
pens, cephs, imipenem, clauvaunate
DI of quinupristin/dalfopristin
potent inhibitor of CYP3A4
other infections of streptococcus pneumoniae
endocarditisarthritisperitonitis (inflammation of intestines) usually following bloodstream infections
-trick antibiotics to bind here instead-run interference against antibiotics -important form of resistance -"tie up penicillins"
Pseudomembraneous colitis is a serious adverse effect in up to 10% of patients treated with
What antibiotics are 30s ribosome inhibitors? (3)
which three drugs are NNRTIs..because other protease inhibitor also have vir in the name.
B-lactam Mechanism
Inhibit transpeptidation and activate autocatalytic enzymes; weakens PG cell wall causing osmotic imbalance/lysis
Name 3 tetracyclines.
1) tetracycline2) Oxytetracycline3) Doxycycline
Resistant to betalactamases. Used IV against gram- rods. No cross-allergenicity with penicillins or cephalosporins
aminoglycides gen info
Aerobic gram -
extremely polar-so IV
Tetracyclines MOA
binds 30S-directly blocks A site->prevents protein synthesis

aztreonam MOA
-irreversibly inhibits PBP-3 which forms septum during bacterial division
T/F First Generation Cephalosporin may be used as alternative therapy in pts allergic to penicillin (depends on sensitivity to penicillin).
What Antibiotic class is a semi-synthetic derivative from a fungus?
Cefixime, Cefpodoxime
Cephalosporins-3rd gen, gm-, less gm+
Active against penicillin resistant S. pneumoniae?
Tetracycline (Protein sys. 30S) - Minocycline
Antibiotics that work by molecular mimicry.
Adverse rxn with ticarcillin?
platelet function abnormalities
Neomycin is used topically for minor soft tissue infections combined with what two drugs?
Which class of drugs may cause seizures?
gram negative bacilli (enterobacteriaceae)
enteric bacilli, aerobes-large, diverse group ofgram neg rods found in nature and as part ofthe nromal flora of man and animals-most are upportunistic pathogens but some strains are highly and specifically pathogenic (E coli)-colonization of the human GI tract but can cause disease-colonization of human GI tract but can rarely cause disease-do not colonize the GI tract but do cause disease when present-Salmonella, shigella, some E. coli, and yersinia species are truely pathogenic-causative organisms of gram - species-lipo-polysaccharide (endotoxin) contained in cell wall and is the initiating (virulence) factor in development of gram - sepsis-enteric common antigen-chromosomal and plasmid mediated resistance to antibiotics is common and treatment is guided by results of cultures and sesitivities (susceptibility)
infection of soft tissue around the nails-brought on by banging the nail, damage under the nail, blood under nail, good growth medium, usually fungus, breaks down skin even more, s. ep. colonizes, cephalitis
Antiviral for influenza A and B.Only oral.Eliminated by kidneys.
What does vancomycin cause if administered with other drugs toxic to this organ?
renal impairment
Lyme disease --what is the tx.what could tx diphteria?
Bactericidal Antibiotics that are Concentration-dependent (4)
Aminoglycosides, quinolones, lipopeptide, ketolides
Example of beta-lactam antibiotics?
PCNs, cephalosporins, carbapenems (imipenem), monobactams (aztreonam)
Uses of vancomycin
MRSA, enterococci, C. difficile (backup drug)
NOT a quinolone or a fluroquinolone, but similar MOA

targets Beta subunit of DNA gyrase->inhibits the ATP dependent relax. of bacterial DNA
sulfonamide hematopoietic reactions
-hemolytic anemia in glu-6-phosphate dehydrogenase deficiency (G6PDD)

-agranulocytosis is rare
True/False. Are your chances higher to get Achilles Tendon Rupture when Quinolones are taken?
Macrolides, gm+, gm- (H. flu), genital pathogens
ABx with Hep Dsyfx dose changes [8]
*Ethambutol, isoniazid – Mycobacterium -Mycobacteria have an unusual cell wall which includes mycolic acid. Drugs which inhibit synthesis of mycolic acid synthesis are toxic to mycobacteria. This provides an effective and very narrow spectrum treatme
*Metranidazole – obligate anaerobes (and some parasites)-Obligate anaerobes posses an enzyme activity that processes metranidazole into a toxic product
carboxy pens and ureido pens
ticar and piperciliin
Which cephalosporin is used below the diaphragm for GI?
How are AGs excreted?
excreted entrirely through glomerular filtration
half life of 2-3 hr; greatly increased in renal disease and required dosing adjustment
Interstitial Nephritis
What is the adverse reaction to Beta-lactams that is an allergic reaction that manifests itself in the kidney?
beta-lactamase inhibitor
What class of drugs is Calvulanic acid?
Prevention of Streptococcus pneumoniae
-Prevention -vaccine developed against most common disease producing capsular antigens -high risk patients:elderly >65 yr, underlying diseases affecting immune status
what % of people are sensitive to penicillin
What are two examples of 1st generation cephalosporins?
cephalexin (Keflex)
which drug is shown to reduce vertical transmission of HIV.
Staph epidermis is most often seen clinically as ___?
line infections
Drugs that inhibit viral DNA polymerases
Acyclovir, foscarnet, ganciclovir
what to use for uncomplicated/complicated UTI's
S.E. of clindamycin
hypotension and cardio collapse when IV infused too fast

Antibiotic associated Psuedomembranous colitis(AAPC)

2nd gen ceph's
Use: respiratory disorders + UTI; rarely 1st line

-G+ (just a little less than 1st gen)

-G- "Please Enter the National Institute of Mental Health"
Proteus mirabilis
Neisseria gonorrhea
Indole + proteus
Which generation of cephalosporin acts primarily against Gram +?
First Generation Cephalosporin
Fluoroquinolones spectrum
excellent gm- (H. flu), decent gm+, shigella, salmonella
These drugs inhibit nucleic acid synthesis
Rifampin, Quinolones, Metronidazole
aminopen Coverage
broad spectrum: not effective vs. beta lactamase producers. both acid resstant - amox better absorbed even w food
does not bind pp as much as predecessors
ecerted through kidneys
Tetracyclines have good activity against...
good activity vs. unusual spp.
intracellular organisms (highly active vs. spirochetes, mycoplasma, chlamydia, and rickettsia)
You have a pt who is diagnosed with Herpes zoster at age 65, what drug would you put them on?
Treatment of neisseria meningiditis
high dose penicillin G, alternative 3rd generation cephalosporins, chloramphenicol
Common illnesses Tx with antivirals
Chicken pox (varicella), shingles (zoster), genital herpes (herpesviridae), Influenza.
gentamicin mechanism of action
Bacteriocidal. Must get to 30s ribosome by entering the cell, cell-wall breakdown by cell wall active agents helps it get through.
Isoniazid (INH) MOA
INH probably works by inhibition of the biosynthesis of mycolic acids, unique constituents of the mycobacterial cell wall
MOA of polyenes
Formation of artificial pores in the ergosterol membranes disrupts membrane permeability
tetracyclines mech for selectivity
taken up by energy-dependent process in prokaryotic cells only
how is vancomycin resistance developed
bacteria replace D-Ala-D-Ala with D-Ala-D-lactate, so vancomycin doesn't recognize mutation

VRE (vancomycin-resistant enterococci) use this mechanism
What is the mechanism of Tetracycline?
Bacteriostatic, which inhibit bacterial growth
What is the drug of choice to treat otitis media?
What is used to treat diptheriae (C. diptheriae)
erythromycin + antitoxin
Gram (+): 1st and 4th generation
Gram (-): 3rd generation
Which generation of Cephalosporins is most active against Gram (+) bacteria? and Gram (-) bacteria?
should MIC be reported?
may find need to take into consideration, numbers may be misleading-the general practice=don't report it
what are quinolones active against
give, enteric g-ve rods (pseudomonas), g-ve cocci, mycobacteria
p-amino salycylic acid and sulfones
PABA antagonists used primarily in therapy of Mycobacterium infections
topical use for burns
silvadine - topical sulfa drug with silver
(AG) if one drug doesn't work.....
try another...susceptability to the conjugating ezymes differs
specific mechanisms of penicillin resistance (2)
1. failure to reach PBPs
2. porin-deficient mutation
What are Aminoglycosides used to kill?
Gram – bacterias (Pseudomonas, Proteus, E. coli, Klebsiella, Serratia) (PPEKS)
Where in the body can the malaria organism be found?
liver & RBCs
1st generat cephs
good for staph and strep and soft tissue infections
neisseria gonorrhea
-1 mill new cases ev yr, prob a severe underestimate-transmission by sexual contact, maj reservoir in asymptomatic infected persons-highest incidence among 20-24yrs of age-50% of women are infected after sigle exposure -50% of women are asymptomatic, 15% may develop PID, fallopian scarring, sterility, ectopic pregnancy-20% of men are infected after single exposure -10% are asymptomatic, -Chlamydia trachomatis is oftentime a co-infection and should also be treated
What is the mechanism of PNC?
binds to the transpepsidase and acylates it
Ribavirin is used for which viruses?
RSV Influ A and BHep C
when do you discontinue PZA
D/C from multi-drug regiemn after the 2nd month
What are the side effects of Quinolones in the other systems?
fever, chills, blurred vision, tinnitus
Damage bacteria cell wall / Broad Spectrum (G+ & G-) / More G-, less G+ / Newer Ceph's are costly / Cross sensitive to PCN / IV site change q24-48 hours to preven phlebitis / Superinfections common <opportunistic yeast infections>
ceph - 3rd gen ther uses
bac meningitis
lyme disease
life threatening sepsis
E. coli & K. pneumoniae
If you see which two bacteria would you then look for ceftazidime and for an ESBL?
What two drugs inhibit the formation of peptidoglycan units?
Vancomycin and Bacitracin, also the Beta lactams inhibit cross linking of linear peptidoglycan strands (includes the Penicillins and Cephalosporins)
Name the top 3 most common organisms found in 1) larynx, trachea, and bronchi, and 2) lungs. (from most freq to less)
resp viri, strep pneumoniae, mycoplasma pneumoniae

strep pneumoniae
haemophilus influenzae
mycoplasma pneumoniae
ceph's with MTT (methylthiotetrazole) side chain
&quot;i MET a TAN MAN in the endZONE&quot;

-cefMETazole (2nd gen cephamycin)
-cefoteTAN (2nd gen cephamycin)
-cefMANdole (2nd gen ceph)
-cefoperaZONE (3rd gen ceph)

1. bleeding - inhibits conversion of prothrombin to thrombin; co-admin vitamin K
2. disulfuram-like reactions with EtOH
types of people who are at high risk to develop TB
HIV patients, immunocompromised patients & homeless
What bacteria is erythromycin active against and what is it inactive against?
active vs group A and B streptococci, S. viridans, and penicillin-sensitive S. pneumoniae
ineffective vs. enterococci
active vs C. diptheriae and Bordatella pertussis (whooping cough)
what a important podiatric ae ass with ciprofloxacin
its a quinolones so achilles tendonitis
what is a major side effect of imipenem
Seizures at high serum levels, especially in renal insufficient pt.
how does failure to reach PBP confer penicillin resistance
-B-lactam antibiotics must pass thru G- envelope via porins to reach target site
-agents unable to pass thru porins can't cross envelope thus ineffective for G-
What may a patient want to avoid when taking a cephalosporin? Why?
Alcohol; produces GI distress, hypotension, tachycardia, SOB
which of the following is not true of vancomycin?inhibits prtein synthesis.has a narrow spectrum against Gram + & anaerobic organisms, sounds like an aminoglycoside but isn't. causes oto & nephrotoxicity.
inhibit pretin sythesi, it inhibits cell wall sythesis
how is AG selective? not affecting human tissue...
we have 80S ribs. and eukaryotes don't have transp mechs for AG's
Should tetracyclines be taken with a full glass of water and be given at bedtime?
take with a full glass of water, do not give at bedtime
which generation ceph's can penetrate CNS
3rd and 4th gen CAN X BBB
1st and 2nd gen CAN'T X BBB
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