Beta lactam antibiotics Flashcards
Quiz 1
What are the types of ß-lactam antibiotics?
- penicillin
- cephalosporin C
- carbapenems
- monobactams
what is the mechanism of action for ß-lactam antibiotics ?
- inhibits bacterial cell wall synthesis
- binds to PBP to interfere w/ transpeptidation rxn - bactericidal action
what enzyme does ß-lactam antiobitics inhibits ?
transpeptidase enzyme
what is the function of transpeptidase enzyme ?
mediates cross linking of peptidoglycan strands w/. penicillin binding proteins
what are the microbial resistant beta lactam antibiotic?
- production of beta lactamase enzyme
- permeability of cell wall
- reduce sensitivity of penicillin binding protein
What are beta -lactam antibiotic only effective against ?
synthesized peptioglycan
what are the classification for penicillin ?
- natural penicillin
2. semi-synthetic
what are the types of semi-synethtiec penicillins?
- penicillinase -restant penicillin
- broad -spectrum penicillin
- extended spectrum /anti-pesudomonal penicillin
what are the type of natural penicillin?
- penicillin G
2. penicillin V
what is the microbial susceptibility of natural penicillin?
narrow spectrum
How is Penicillin G administered ?
parenteral
How is penicillin V administered ?
orally
-acid stable
What species of Gram + can treated with natural penicillin G of beta lactam ?
- streptococci
- staphylococci
- Corynebacterium
- L.monocytogenes
- P.multocida
- haemophilus influenzar
what type of staphylococci can not be treated with penicillin G ?
non-penicillinase producing sp.
what types of bacteria can penicillin G treat?
- Anaerobic gram +
- Anaerobic gram -
- spirochetes
what species of anaerobic gram - species can be treated with penicillin G?
- clostridium
- fusobacterium
- bactericides
what species of spirochetes can be treated with penicillin G ?
- borrelia
2. leptospira
what are the dosage forms of natural penicillin ?
- Na/k salt
- procaine penicillin
- benzathine penillicin
what does Na/K salt natural penicillin produces what ?
crystalline penicillin injection
what does procaine penicillin produce ?
long acting penicillin
what does Benzathine penicillin produce ?
repository preparation ( IM/intra-mammary )
what semi-synthetic penicillin has good stability against bacterial beta lactase enzyme ?
penicillinase resistant penicillin ( isoxazolyl penicillin
what are the compound of penicillinase resistant penicillin has good oral absorption ?
acid stable
- cloxacillin
- oxacillin
- dicloxacillin
what compounds of penicillinase resistant penicillin has poor oral absorption ?
- Nafcillin
2. methicillin
what is the microbial suspectiility of penicillinase resistant penicillin?
- penicillinase producing staphylococcus sp.
2. bacterial infection of eye
what bacterial species do you use penicillinase resistant penicillin ?
bovine staphylococcal mastitis
what type of bacterial species are penicillinase restart penicillin used for bacterial infection of the eye ?
- staphylococcus sp.
2. bacillus sp
what type of penicillinase restart penicillin is used for bacterial infection of the eye ?
benzathine cloxazillin
what are the types of broad spectrum penicillin ?
beta-lactamase sensitive
- amoxicillin
- ampicillin
what are the prodrug forms of ampicillin?
- bacampicillin
- hetacillin
- pivampicillin
- talampicillin
what is the microbial suspectibility of broad spectrum penicillin?
- microbe susceptible to natural penicillin
2. Entrobacteriaceae
what are the species of Enterobacteriaceae that broad spectrum penicillin can be treated with?
- e.coli
- proteus mirabilis
- salmonella
what should be administered with broad spectrum penicillin?
beta lactamase inhibitors
what are the types of extended spectrum/anti-pseudomonal penicillin of semi-synthetic penicillin ?
- Ticarcillin
- Carbenicillin
- Piperacillin
- mezlocillin
- azlocillin : beta-lactamase sensitive
what is the microbial susceptibility of extended spectrum penicillin?
broad spectrum
- gram - aerobic & anaerobic
- Enterobacteriaceae
- bactericides fragilis
what species of gram - aerobic & anaerobic microbe can be treated with extended spectrum penicillin?
- E.coli
- proteus mirabilis
- salmonella
- Pseudomonas sp.
what should be administered with extended spectrum penicillin ?
beta -lactamase inhibitor
what is the pharmacokinetics of penicillin for absorption?
- formulated as Na/K salt ( crystalline pencilline)
2. administered : oral/parental/intramammary route
what type of penicillins are administered orally?
- penicillinase resistant penicillin
- pencillin V
- aminopenicillins
What happen if food is given with penicillin V & penicillinase restart penicillin ?
decrease
what is pharmacokinetics for absorption of aminopencillin?
- oral
- IM
- SC
- suspension in oil
What amino penicillin is more acid stable & has complete absorption ?
amoxicillin
what is the oral bioavailability for amoxicillin ?
60- 70%
what is the oral bioavailability for amPICILLIN ?
30- 40 %
-Ester form increase bioavailability
How is absorption of amino penicillin administered IM/SC route ?
rapid
how is absorption of aminopenicillin administered in suspension in oil?
prolongs absorption for 18 hrs
How is absorption of berzathine penicillin G ?
prolonged for more than 7 days
what is the caution for procaine penicillin G?
never administered by IV route → affects cardiac conduction system
what is the caution for benzathine penicillin G?
repository should be administered by IM route
what is the distribution of penicillin ?
- weak organic acid → ionized in plasma
- distributed in ECF
- low permeation to CNS
- sufficient concentration attained in synovial fluid, skin, soft tissues ,visceral organs
- distributed in milk of lactating animals
what is the distribution for semi-synthetic groups ?
permeates more through cell membrane
what is the percentage for cloxacillin & nafcillin?
80%
what is the percentage for penicillin G ?
60%
what is the percentage for ampicillin?
20%
what is the pharmacokinetics of penicillin for metabolism ?
- only 20% of administered dose undergoes metabolism
2. peniclloic acid metabolite → allergic rxn
what is the pharmacokinetics of penicillin for excretion?
- by kidney:
- glomerular filtration
- proximal tubular secretion - interaction w/ probenecid
How is nafcillin excreted ?
bile
what are the adverse effects of penicillin Ty?
- anaphylactic rxn
- superinfection
- convulsion/ataxia
- anaphylaxis & CNS disorder
- excitement
- acute cardiac toxicity
what animals would you see convulsion/ataxia from sodium benzyl penicillin ?
dogs
cats
what animals would you see anaphylaxis & CNS disorders from procaine penicillin?
- rodent
- birds
- snakes
- turtles
what animal would you see excitement from procaine penicillin ?
horses
what type of penicillin can cause acute cardiac toxicity from IV administration ?
procaine /potassium penicillin salts of penicillin G & ampicillin
What is cehalosporin?
- semisynthetic ß-lactams
- more resistant to ß-lactamase
- classified base on spectrum
what are the classification of cephalosporin ?
- 1st generation
- 2nd generation cephalosporin
- 3rd generation cephalosporin
- 4th generation cephalosporin
what are types of first generation cephalosporins ?
- Cefadroxil
- cephalexin
- cafazolin
- cephalothin
- Cephapirin
- cefalonium
what first generation cephalosporins can be given orally?
- cefadroxil
2. cephalexin
what first generation cephalosporins can be given parenterally?
- cefazolin
2. cepharirin
what first generation cephalosporin is used as a ophthalmic ointment in dogs as well as intramammary for cattle ?
Cefalonium
what is microbial susceptibility for first generation cephalosporins?
- Gram + bacteria
2. gram - bacteria
what are the species of gram + bacteria that is susceptible to first generation cephalosporin ?
- corynebacteria
- streptococci
- staphylococci ( beta lactamase positive)
what are the species of gram - bacteria that is susceptible to first generation cephalosporin ?
- E.coli
- Klebsiella pneumonia
- H. influenzae
- P. mirabilis
- Actinobacillus
- Pasteurella
- Salminella
what first generation cephalosporin is very effective in treating Salmonella ?
cefazolin
what are the second generation cephalosporins?
- Cefaclor
- Cefotetan
- Cefoxitin
- Cefuroxime
what second generation cephalosporins is given parenterally that is grouped in the cephamycin group?
- cefotetan
2. Cefoxitin
what second generation cephalosporins can be given orally ?
cefaclor
what 2nd generation cephalosporins can be given orally or parenterally & crosses the blood brain barrier?
Cefuroxime
Cefotetan & Cefoxitin treat what type of microbes?
anaerobic microbes
what is the microbial susceptibility for 2nd generation cephalosporins ?
- antibacterial action gram - bacterial infection
- anaerobic bacteria (septic peritonitis)
- Bacteriodes fragilis ( Cefoxitin & cefotetan
- more resistant to cephalosporinase
what are 3rd generation cephalosporins?
- Cefixime
- Cefoperazone
- cefotaxime
- ceftiofur
- Ceftazidime
- Cefovecin
- Cefpodoxime Proxetil
what 3rd generation cephalosporins can be administered orally ?
- Cefixime
2. Cefpodoxime Proxetil
what 3rd generation cephalosporins can be administered parenterally?
- cefoperazone
- Cefotazime
- Ceftiofur
- Ceftazidime
- Cefovecin
what 3rd generation cephalosporin is used to treat Pseudomonas sp.?
Cefoperazone
what 3rd generation cephalosporins is used to treat Pseudomonas species & other gram - bacteria in exotic & zoo animals?
Ceftazidime
what 3rd generation cephalosporins are used in dog & cats for skin/pyoderma/ UTI infections?
- Cefotaxime
2. Cefovecin
what 3rd generation cephalosporins has a long 1/2 life that can be given as a single infection to treat skin/pyoderma/UTI infections?
Cefovecin
what 3rd generation cephalosporin is prodrug esters that metabolism in vivo & will release active drug ?
Cefpodoxime Proxetil
what is the microbial susceptibility of the 3rd generation cephalosporins ?
- most effective gram -
2. resistant bacterial organisms to other generation cephalosporins
what are the species of gram - bacteria that can be treated by 3rd generation cephalosporins ?
- E.coli
- Enterobacter
- Klebsiella
- Proteus
- Serratia
- Pseudomonas
what 3rd generation cephalosporin has a broader gram + activity & active against ß-lactamase producing bacteria & anerobes ?
Ceftiofur
what is Ceftiofur metabolized in vivo as ?
Desfuroylceftiofur ( active )
what are the indications for Ceftiofur?
- Respiratory tract infection (cattle & pigs)
- UTI (dogs)
- Respiratory tract infection , pleurites & peritonitis ( horses)
- E.coli infection ( poultry)
what are the 4th generation Cephalosporins ?
- Cefepime
2. Cefquinome
what generation of cephalosporins is used when there is an completely resistance bacterial infection?
4th generation
what is microbial susceptibility for the 4th generation cephalosporins ?
- Broad spectrum
- more resistant to ß-lactamase
- effective against resistant infection
what are the species of bacteria that 4th generation cephalosporins are used on ?
- gram + cocci
2. gram - bacilli & pseudomonas aeruginosa
what are the pharmacokinetics in absorption for cephalosporins ?
- well absorbed orally & parentally ( IM / SC)
2. bioavailability depends on drug & species
what cephalosporins have higher oral absorption ?
- Cephalexin
2. Cefaclor
what is the pharmacokinetics in distribution for cephalosporins ?
- attains high concentr. in many areas of the body
2. penetrates the CSF
Where does cephalosporins maintain high concentration in the body?
- blood
- urine
- bile
- pleural fluid
- synovial fluid
- pericardial fluid
- cortical bone
- cancellous bone
what 2nd generation cephalosporins penetrates the CSF ?
Cefuroxime
what 3rd generation cephalosporins penetrates the CSF ?
- Ceftriaxone
- Ceftoaxime
- Ceftazidime
- Ceftizoxime
what is the pharmacokinetics in metabolism for cephalosporins ?
liver metabolizes to form dactyl derivatives
what is significant about the deacetylated metabolite of cefotazime ?
- active metabolite
2. longer half life parent cmpd
what is the pharmacokinetics in excretion for cephalosporins ?
kidneys excrete by :
- glomerular filtration
- Proximal tubular secretion
what cephalosporins are not excreted by the kidneys ?
- Ceftriaxone
2. Cefoperazone
what are the side effects for cephalosporins ?
- Local tissue rxn at injected site
- Hypersensitivity rxn
- GI signs : V/D in small animals
what are the side effects of Ceftiofur at high doses in dogs ?
- anemia
2. Thrombocytopenia
what is the side effects of Cephalothin & cefmetazole ?
decrease platelet aggregation
what are Betalactamase inhibitors?
- Clavulanic acid
- Sulbactam
- Tazobactam
what is pharmacokinetics for clavulanic acid as a betalactamase inhibitor?
- Betalactam ring in structure
- competitive inhibitor of betalactam antibiotic
- attaches to catalytic center of beta lactamase prevent degradation of administered penicillin
what are type of clavulanic acid as betalactamase inhibitors?
- Amoxicillin + potassium clavulanate
2. ticarcillin _potassium clavulanate
what is the pharmacokinetics of sulbactam as betalactamase inhibitor?
- pencillanic acid sulfone
- increase antimicrobial activity
- not absorbed orally
what is a type of sulbactam as a betalactamase inhibitor?
- sodium sulbactam (parenteral preparation)
2. ampicillin (IV/IM/SC)
what is the pharmacokinetics of tazobactam as a betalactamase inhibitor ?
- used in combination w/ piperacillin for IV use
2. treat resistant Pseudomonas aeruginosa
what are other betalactam antibiotics ?
- Carbapenems (penems)
- Meropenem
- Monobactams
what is a type of carbapenems used as a betalactam antibiotic ?
Imipenem
what is the pharmacokinetics off Imipenem?
- stable against ß-lactamase enzyme
- administered w/ cilastatin
- broadest spectrum of action
- rapid bactericidal ; post antibiotic effect
what is the microbial spectrum for Imipenem for other betalactam antibiotics?
- gram - aerobic & anaerobic bacteria
2. serious resistant infection
what is a type of Imipenems used ?
Imipenems + Cilastatin
what is the adverse effect for Imipenems + cilastatin ?
seizures
what is the pharmacokinetics for meropenem as betalactam antibiotic ?
- more soluble
2. decrease incidence of adverse rxn
what is the pharmacokinetics for monobactam?
- monocyclic beta lactam antibiotic
- gram - aerobic bacteria & pseudomonas aeurginosa
- stable against beta lactamase hydrolysis
- poor inducer of bet a lactamase production
- used in PT that are allergic to penicillin