PHM203 Pharmacology – Questions & Accurate
Solutions (Verified)
Spectrum of Coverage for natural penicillin (penicillin G, penicillin K) Right
Ans - GP > GN
Spectrum of Coverage of aminopenicillin (amoxicillin, ampicillin) Right Ans
- GP and enterococcus (GN)
Spectrum of Coverage penicillinase resistant penicillins (cloxacillin,
methicillin) Right Ans - GP
Spectrum of Coverage of extended penicillin (piperacillin) Right Ans - more
GN activity
Spectrum of Coverage of Penicillin + Beta Lactamase inhibitors (amoxiclav,
piperacillin/tazobactam) Right Ans - GP (including enterococci), GN,
anaerobes
Key pathogens of natural penicillin Right Ans - strep p, syphilis, GP oral
anaerobes, N. meningitides
Key pathogens of aminopenicillins Right Ans - staph a, listeria
Key pathogens of penicillin resistant penicillinase Right Ans - strep, H.
influenzae, E. Coli
Key pathogens of extended penicillins Right Ans - P. aeruginosa, gut
anaerobes
Key pathogens of penicillins + BL inhibitors Right Ans - amoxiclav: H.
influenzae, some E. Coli
piper/tazo: B. fragilis, enterobactericae
Adverse effects of penicillin in general Right Ans - neurologic effects
- irritability, seizures
, GI effects
- NVD
Allergic/hypersensitivity rxn
- anaphylaxis, drug induced fever, serum sickness, rashes, etc
note that there is less adverse effects in the extended spectrum class
MOA of penicillin Right Ans - cell wall synthesis inhibitor that binds to PBP.
They all have a core beta lactam ring, and the difference between the drugs is
the side chain. The bond angle makes it very easy to break when bound to PBP
which causes cell wall to break apart.
Which penicillins are resistant to beta lactamase Right Ans - natural
penicillins, aminopenicllins, extended penicillins
resistance mechanisms used by penicillin (4 mechanisms) Right Ans - -
inactivation by beta lactamase
- modification of target PBPs
- impairing penetration to reach PBP
- efflux transporters
does AUC:MIC matter in beta lactams? Right Ans - no
What is the spectrum of activity of all cephalosporins except 5th gen
cephalosporins Right Ans - The lower the generation, the more GP activity,
the higher the generation the more GN activity
They all have GP and GN activity, but 5th gen has weak GN activity
examples of 1st gen cephalosporins Right Ans - cephalexin
cefadroxil
cefazolin
examples of 2nd gen cephalosporins Right Ans - cefuroxime
cefaclor
cefprozil
cefoxitin
Solutions (Verified)
Spectrum of Coverage for natural penicillin (penicillin G, penicillin K) Right
Ans - GP > GN
Spectrum of Coverage of aminopenicillin (amoxicillin, ampicillin) Right Ans
- GP and enterococcus (GN)
Spectrum of Coverage penicillinase resistant penicillins (cloxacillin,
methicillin) Right Ans - GP
Spectrum of Coverage of extended penicillin (piperacillin) Right Ans - more
GN activity
Spectrum of Coverage of Penicillin + Beta Lactamase inhibitors (amoxiclav,
piperacillin/tazobactam) Right Ans - GP (including enterococci), GN,
anaerobes
Key pathogens of natural penicillin Right Ans - strep p, syphilis, GP oral
anaerobes, N. meningitides
Key pathogens of aminopenicillins Right Ans - staph a, listeria
Key pathogens of penicillin resistant penicillinase Right Ans - strep, H.
influenzae, E. Coli
Key pathogens of extended penicillins Right Ans - P. aeruginosa, gut
anaerobes
Key pathogens of penicillins + BL inhibitors Right Ans - amoxiclav: H.
influenzae, some E. Coli
piper/tazo: B. fragilis, enterobactericae
Adverse effects of penicillin in general Right Ans - neurologic effects
- irritability, seizures
, GI effects
- NVD
Allergic/hypersensitivity rxn
- anaphylaxis, drug induced fever, serum sickness, rashes, etc
note that there is less adverse effects in the extended spectrum class
MOA of penicillin Right Ans - cell wall synthesis inhibitor that binds to PBP.
They all have a core beta lactam ring, and the difference between the drugs is
the side chain. The bond angle makes it very easy to break when bound to PBP
which causes cell wall to break apart.
Which penicillins are resistant to beta lactamase Right Ans - natural
penicillins, aminopenicllins, extended penicillins
resistance mechanisms used by penicillin (4 mechanisms) Right Ans - -
inactivation by beta lactamase
- modification of target PBPs
- impairing penetration to reach PBP
- efflux transporters
does AUC:MIC matter in beta lactams? Right Ans - no
What is the spectrum of activity of all cephalosporins except 5th gen
cephalosporins Right Ans - The lower the generation, the more GP activity,
the higher the generation the more GN activity
They all have GP and GN activity, but 5th gen has weak GN activity
examples of 1st gen cephalosporins Right Ans - cephalexin
cefadroxil
cefazolin
examples of 2nd gen cephalosporins Right Ans - cefuroxime
cefaclor
cefprozil
cefoxitin
