ANTIBACTERIAL AND ANTI-INFECTIVE AGENTS (PART 1) Flashcards
kills bacteria, without host defense mechanisms
bactericidal
inhibits microbial growth, requires hosts defense mech, does not kill bacteria
bacteriostatic
minimum inhibitory concentration
lowest concentration needed for inhibiting growth
- targets the cell wall of the organism
- selectively interfere with the synthesis of the cell wall
beta-lactam antibiotics
- binds to PBPs
- inhibition of transpeptidases
- production of autolysin
penicillin
classification of penicillin:
pen g - IV
pen v - ORAL
narrow spectrum
classification of penicillin:
nafcillin
oxacillin
cloxacillin
dicloxacillin
very narrow spectrum
classification of penicillin:
ampicillin
amoxicillin
extended spectrum
classification of penicillin:
sulbenicillin
carbenicillin
ticarcillin
piperacillin
antipseudomonal
classification of penicillin:
targets gram-positive except:
- penicillinase prod. bacteria
- meningo
- spirochetes
- anaerobic
narrow spectrum
dose for syphilis
PEN G
2.4 million units IM - single dose
prophylaxis for rheumatoid fever
PEN V
2500 mg - PO BID
classification of penicillin:
targets most penicillinase prod. staphylo
vary narrow
dosage for cellulitis (very narrow)
CLOXACILLIN
500 mg - QID
classification of penicillin:
targets gram-positive
- cocci
- enterococci
- l. monocytogenes
extended spectrum
dosage for cellulitis (extended)
AMOXICILLIN
500 mg - TID
most important adverse reaction of penicillin
hypersensitivity
all adverse reactions of penicillin
HDN-NHC
hypersensitivity
diarrhea
nephritis
neurotoxicity
hematologic toxicities
cation toxicity
nursing implication for penicillin:
carefully monitor for at least ___ minutes after administration
30
nursing implication for penicillin:
oral penicillin effectiveness is decreased when taken with?
- caffeine
- citrus fruit
- cola beverages
- fruit juices
- tomato juice
- similar to penicillin in structure
- 7 aminocephalo-sporanic acid
- more stable to may bacterial betalactamases
- broader spectrum
- 5 generations
- less susceptible to penicillinases
cephalosporins
what generation of cephalosporins:
- cefazolin
- cephalexin
1st gen
what generation of cephalosporins:
- cefoxitin
- cefaclor
- cefuroxime
2nd gen
what generation of cephalosporins:
- ceftriaxone
- ceftazidime
- cefixime
3rd gen
what generation of cephalosporins:
cefepime
cefpirome
4th gen
what generation of cephalosporins:
ceftobiprole
ceftaroline fosamil
5th gen
what generation of cephalosporins:
targets gram positive cocci, inclu penicillin resistant s. aureus, except:
- MRSA
- MRSE
also targets SOME gram negative bacili
- e coli
- k. pneumonia
- p. mirabilis
1st gen
prophylaxis for cardio and general surgeries
CEFAZOLIN
1-2g IV - single dose pre-op
dosage for respiratory infections
CEPHALEXIN
250 mg - PO q6
what generation of cephalosporins:
improves activity against:
- h. influenza
- m. catarrhalis
- n. meningitids
- n. gonorrhea
enahnced against staphy, non entero, and some entobacteriaceae
2nd gen
prophylaxis for non perforated appendicits
CEFOXITIN
1-2g IV - pre-op
dosage for pharyngitis or tonsillitis
CEFUROXIME
250 mg - PO Q12 for 10 days
common adverse reaction of cephalosporin
allergic manifestations
adverse reaction of cephalotin (cephalosporin)
nephrotoxicity (high doses = acute tubular necrosis)
adverse reaction of cefamandole, cefotetan, cefoperazone (cephalosporin)
disulfram-like reactions (similar to when alcohol is taken)
nursing implications for cephalosporin
orally administered should be given (before / after) meals to decrease GI upset
after
- 5 member ring system
- different from penicillin by being saturated and containing a CARBON atom, instead of sulfur
- broad spectrum
- drug of choice for enterobacter infections (resistant to beta lactamase)
carbapenems
- interact with PBPs, induces formation of long, filamentous bacterial structure
- extremely resistant to beta lactamases
monobactam
carbapenem / monobactam?
- meropenem
- imipenem
- ertapenem
carbapenem
carbapenem / monobactam?
used for nosocomial infections caused by resistant polymicrobial infections caused by gram + and - organisms, anaerobic bacteria and ESBL + organisms
carbapenem
carbapenem / monobactam?
aztreonam
monobactam
carbapenem / monobactam?
activity limited to gram (-) bacili:
- enterobacteriaceae
- aeromonas sp
- n. gonorrhea
- h. influenza
- p. aeruginosa
monobactam
dosage for intraabdominal infections
- MEROPENEM - 1g - IV q8
- IMIPINEM - 500 mg - IV q6 OR 1g IV q8 for 4-7 days
dosage for pseudomonal infections
AZTREONAM
2g IV/IM q6-8
carbapenem / monobactam?
side effects:
- nausea and vomiting*
- seizures
- cross-sensitivity allergic reactions
carbapenems
carbapenems is contraindicated to people with?
epilepsy
carbapenem / monobactam?
side effects:
- streptococcus and enterococci superinfections
- elevation of transaminases
- cause abnormal liver function test
monobactam
- resemble beta-lactam molecules, weak antibacterial
- may inhibit beta lactamases thus protecting penicillin from inactivation
- fixed combinations with specific penicillins
beta lactamase inhibitors
clavulanic acid is usually paired with?
AMOXICILLIN or TICARCILLIN
sulbactam is usually paired with?
AMPICILLIN
tazobactam is usually paired with?
PIPERACILLIN
dosage for exacerbation of chronic bronchitis
CO-AMOXICLAV
1g BID
dosage for severe infections; nosocomial pneumomia
PIPERACILLIN / TAZOBACTAM
4.5g IV q6
other cell wall inhibitors:
inhibit cell wall mucopeptide formation by binding D-ala-D-ala portion of cell wall percursors
vancomycin
other cell wall inhibitors:
active against MRSA, MSSA, coagulase-negative staphy, enterococci, streptococci, c. diptheria, c. difficile, and listeria
vancomycin
dosage for vancomycin for MRSA
VANCOMYCIN
15-20 mg/kg IV q12
side effects of vancomycin
- phlebitis at injection site
- red man / red neck syndrome
block 30s subunits to block binding of aminoacyl-tRNA to acceptor site ribosome-mRNA complex
tetracycline
classification of tetracycline:
- tetracycline
- oxytetracycline
short acting
classification of tetracycline:
- demeclocyline
- mathacycline
intermediate acting
classification of tetracycline:
- doxycycline
- minocycline
- tigecycline
long acting
tetracycline is usually given to ___ allergic patients with leptospyrosis, syphilis, actinomycosis, tularemia, meliodosis, and skin and soft tissue infection
penicillin
DOXYCYCLINE 100 mg PO BID is given to patients with:
- cervicitis
- nongonococcal infections
- donovanosis
- lymphogranuloma venereum
most important adverse effect of tetracycline
phototoxicity
nursing implication for tetracycline:
milk products, iron, anatcids, and other dairy should be avoided because of the ___ and brug-binding that occurs
chelation
nursing implication for tetracycline:
all medications should be taken with ___ onuces of fluid
6-8
- mainstay for the treatment for aerobic gram negative bacili
- irreversible inhibition of protein synthesis
- once outside the cell, they bind to polysomes (causes misreading)
aminoglycosides
- amikacin
- streptomycin
- tobramycin
aminoglycosides
dosage in addition to antipseudomonal beta-lactam or carbapenem in HAP
AMIKACIN
20 mg/kg day IV
dosage for tuberculosis
STREPTOMYCIN 15
12-18 mg/kg IM per day
adverse effects:
- ototoxicity
- nephrotoxicity
- neuromuscular paralysis
- allergic reaction
aminoglycosides
nursing implications for aminoglycosides:
monitor ___ and ___ blood levels of these agents to prevent nephrotoxicity and ototoxicity
peak and trough
- macrocyclic lactone ring
- prevents translocation at the 50s subunit
- at higher doses, can be bactericidal
macrolides / ketolides
streptomyces erytheus
- drug of first choice
- alternative to penicillin in pts allergic to beta lactam antibiotics
eythromycin
active against aerobic gram positive cocci and bacilli:
- legionella
- mycoplasma
- chlamydia
macrolides / ketolides
dosage for acute bronchitis
AZITHROMYCIN
500 mg PO BID
dosage for cervicitis; chancroid
AZITHROMYCIN
500 mg PO single dose
dosage for chancroid
ERYTHROMYCIN
500 mg PO QID for 7 days
adverse effects:
- GI distress
- cholestatic jaundice
- ototoxicity
macrolides / ketolides
macrolides / ketolides is contraindicated to people with?
hepatic dysfunction
nursing implication for macrolides / ketolides:
absorption if oral ERY is enhanced when taken on an ___
empty stomach
- inhibition of peptide bond formation at the 50s subunit
- blocks binding of the aminoacyl moiety of the charges tRNA molecule to the acceptor site of ribosmal mRNA complex
chlorampenicol
targets aerobic and anaerobic bacteria
chloramphenicol
chlorampenicol is usually given to patients with
fully susceptible typhoid
SEVERE - 100 mg/kg (14-21 days)
UNCOMPLICATED - 50-75 mg/kg (14-21 days)
adverse effects:
- anemia
- gray baby syndrome
- blocks metabolism of warfarin, phenytoin, tolbutamide, and chlorpropamide
chlorampenicol
- chlorine-substituted derivative of lincomycin from s. lincolnensis
- better tolerated than ERY
- distributed well in the body fluids except CSF
- blocks peptide bond formation at 50s ribosomal subunit
clindamycin / lincomycin
dosage for CA MRSA
CLINDAMYCIN
600 mg IV q6-8
dosage for bacterial vaginosis
CLINDAMYCIN cream 2%
1 full applicator (5g) intravaginally HS for 7 days
adverse effects:
- diarrhea
- skin rashes
- impaired liver function
- neutropenia
- antibiotic related colitis
clindamycin / lincomycin
- a mix of 2 streptogramins in a ration of 30:70
- reserved for treatment of vancomycin resistant enterococcus faecium
- interupts protein synthesis by binding on 50s bacterial ribosome
quinupristin / dalfopristin
adverse effects:
- venous irritation
- arthralgia and myalgia
- hyperbilirubinemia
- inhibition of cytochrome p450
quinupristin / dalfopristin
introduced to combat resistant gram positive organisms such as:
- vancomycin resistant s. aureus
- vancomycin resistant e. faecium and e. faecalis
- penicillin resistant strep
synthetic of oxazolidinone
linezolid
- inhibits bacterial protein sythesis by binding at the 70s initiation complex
- it binds to a site on the 50s subunit near the interface with the 30s subunit
linezolid
adverse effects:
- usually well tolerated
- GI upset
- headache
- rash
- thrombocytopenia (if taken > 2 weeks)
linezolid
interfere with bacterial DNA synthesis by inhibiting
- toposomerase II (DNA gyrase) in gram negative organism
- topoisomerase IV in gram positive organism
usually bactericidal against susceptible organisms
exhibit post antibiotic effect
quinolones
adverse effects:
- GI upset
- headache, dizziness
- photoxicity
- connective tissue problems
- QT interval prolongation
quinolones
nursing consideration for quinolones:
should be taken with atleast ___ of fluid per day
3 liters