Pharm 2 - Antimicrobials 3

dalebira's version from 2018-02-04 21:20

Penicillins General

Question Answer
β-lactams are type _________ killing kineticsType 2 - Time dependent (2 helped administer the 1st type of penicillin)
**Are β-lactams ‘cidal’ or ‘static’?Cidal (not part of Mac & Lin's stunt in the pool!)
**What is the mechanism by which Β-lactams work?Inhibits bacterial cell wall synthesis by binding to PBPs (Penicillin Binding Proteins) & stopping Transpeptidase
What are the 3 ways bacteria can become resistant to β-lactams?(1) They make β-lactamase
(2) They can ↓ their permeability
(3) They can ↓ the sensitivity of their PBP
What are the 5 groups of β-lactams?Penicillins
(1 pen in a CAR engine will make a cepha-cepha sound)
β-lactams are only effective against? (Broad def, not specific bact)Effective against rapidly growing organisms that synthesize peptidoglycan
What are the differences btwn the various penicillins? (think structurally)Differences in acyl side chain
Which enzyme is effected by β-lactams?Transpeptidase enzyme
Which penicillin has a stupid long absorption when mixed w/ oil? How long exactly?Benzathine penicillin G, greater than or equal to 7 days (ben was impressive. that G could go for 7 days!)
Highest protein binding pencillins are?Cloxacillin & Nafcillin (80%) (I CLOX'ed NAf upside the head till protein came out)
**Where are penicillins mainly distributed?ECF (cant get into cell, thus narrow spect)
Penicillins have a low rate of distribution to which areas?CSF, aqueous humor & synovial fluid
Milk to plasma equilibrium conc is?1:5
How much of the penicillins are metabolized, & why do we care?20%, which isnt much, but what is metabolized may turn to Penicilloic acid metabolite, which can act as a hapten causing allergic rxns
How are penicillins excreted? Exceptions?Kidney (glom filt & tubular secretion), except Nafcillin is excreted by bile
**How can you ↑ the half-life of penicillins?Admin w/ Probenecid, which competes w/ the penicillin for tubular secretion, so penicillin isn't secreted & keeps cycling in the body (penicillin probenecid)
Which penicillin causes convulsions & ataxia in cats & dogs?Sodium benzyl penicillin ( BEN SO caused a seizure in my dog/cat)
Acute cardiac toxicity caused by which drug?Procaine/potassium penicillin salts (kate is a pro at stopping your heart)
Anaphylaxis & CNS disorders in rodents, birds, snakes & turtles caused by?Procaine penicillin ( "propain" to all the things people tend not to like for some reason)

Natural Penicillins

Question Answer
Broad or narrow spectrum?Narrow (narrow, natrual)
What are the 2 members of the natural penicillins group?Penicillin V & Penicillin G
How can you extend the absorption time of Penicillin G?You can put it in oil (oil is Good)
**Which drugs of penicillin G do you NOT GIVE IV? EVER?Benzathine & Procaine formulations, bc these are repository (IM or intramammary) (BEN is a PRO at KILLING YOUR VEINS)
What are the 2 penicillin G drugs?Benzathine & Procaine (Ben is a PRO G)
**How do you formulate the natural pencillins to be injectable? (IM/SC or IV?)As SALTS!
(1) IM/SC as Na/K salts
(2) IV as Na salts
Which natural penicillins are given orally? Why are they able to be given orally?Penicillin V = oral. (Insert hilarious V-based oral joke gesticulation here). Oral bc they are ACID-STABLE (can survive stomach acid)
Which bacteria are natural penicillins effective against?Strep, Staph (non-penicillinase producing), Gram + and - anaerobic bacteria; Gram + aerobic (Corynebacterium, L. monocytogenes, P. multocida, Haemophilus influenzae)
Which bacteria are natural penicillins NOT effective against?Pseudomonas, Enterobacteriaceae, Staph (penicillinase producing)

Semi-Synthetic Pencillins

Question Answer
What are the 3 groups of semi-synthetic penicillins?(1) Penicillinase-Resistant Penicillins
(2) β-lactamase sensitives aka broad spectrum aka aminopenicillins
(3) Extended spectrum/anti-pseudomonals
Penicillinase-Resistant Penicillins are stable against ___________, which means you can administer them _________acid/bacterial beta lactamase enzyme, orally
Which Penicillinase-Resistant Penicillins have GOOD oral absorption?Oxacillin, Cloxacillin, Dicloxacillin (XXX in the mouth)
Which Penicillinase-Resistant Penicillins have POOR oral absorption?Methicillin, Nafcillin (say "na" to meth, it messes up your ORAL cavity)
Which Penicillinase-Resistant Penicillin is used for ophthalmic formulations?Benzathine Cloxacillin (BEN CLOX you in the EYE)
Which Penicillinase-Resistant Penicillins is excreted in the BILE?Nafcillin
Do Penicillinase-Resistant Penicillins treat bovine mastitis? ExplainYes, bc effective against Penicillinase Producing Staphylococcus sp., (which causes Bovine Staphylococcal Mastitis)
What are the drugs in the Penicillinase-Resistant Penicillins category?Cloxacillin

(cloned oxen dye me (resistant) navy)
What are the 2 β-lactamase sensitive (broad spectrum/aminopenicillins) semi-synthetic penicillins?Amoxicillin, Ampicillin (Don't Mox that Amp, it's sensitive)
Which of the semi-synthetic β-lactamase sensitive (broad spectrum/aminopenicillins) drugs have related esters? Why would we want this?Ampicillin has related esters, which act as pro-drug & ↑ bio-availability.
What are the "pro-drug" forms of Ampicillin? (β-lactamase sensitive semi-synthetics)Bacampicillin
( I am amped to Take pie back home)
**What must you co-administer w/ the β-lactamase sensitive semi-synthetic pencillins? (Aka broad spectrum, aka Aminopenicillins)Admin w/ β-lactamase inhibitors
What are the extended-spectrum/anti-pseudomonal semi-synthetic penicillins? (5)Ticarcillin
(Azlo Been Pipping Me Ticks - extensively)
By what route do you administer extended-spectrum anti-pseudomonal semi-synthetic penicillins?Parenteral route (to extend the dose, dont give orally)
What must you administer w/ the extended-spectrum anti-pseudomonal semi-synthetic penicillins?β-lactamase inhibitors
Semi-synthetic penicillins like to accumulate ___cellularly. Why?EXTRAcellularly, bc they are weak acids so they ionize & it is then difficult to get into the cell
Why do semi-synthetic penicillins have an increased half-life?They are plasma protein bound
How are most semi-synthetic penicillins excreted? Exceptions? Are they changed/metabolized at all?Excreted unchanged via the KIDNEY(urine), except Nafcillin is excreted via the bile, & 20% is changed to Penicilloic acid which may cause allergies
Aminopenicillins are?Broad spectrum penicillins/β-lactamase sensitive pencillins
What are the 2 main Aminopenicllin drugs used?Amoxicillin, Ampicillin (ester forms increase bioavail)
What is the oral bioavailability of Aminopenicillins?Amoxicillin 60-70%
Ampicllin ~20-40%
Suspended Aminopenicllins in oil can prolong their absporption for _________?18 hours
How can semi-synthetic penicillins cause allergies?Approx. 20% of the semi-synthetic pencillins undergo metabolism, & Penicilloic acid is produced which can cause allergic rxns
How can you increase the plasma concentration of semi-synthetic penicillins?You can administer Probenecid, which inhibits the tubular secretion of the semi-synthetic (competitively)
What are the 3 main side effects of semi-synthetics?(1) Allergic rxns (Penicilloic acid)
(2) Superinfxns (kills natural flora & makes room for a worse infxn)
(3) Ataxia/convulsions (GABA Inhibited via Na Benzylpenicillin)
What 2 side effects can Procaine have?(1) Anaphylaxis/CNS in guinea pigs & chinchillas
(2) Excitement in horses
(pro at freaking out horses & choking out rodents)
(3) Acute cardiac toxicity (with pen salts)
Procaine Penicillin G should never be administered by _______ routeIV (affects cardiac conduction system)
Benzathine Penicllin G is a repository and should only be administered in what way?IM route
Broad spectrum penicillins should be administered w/?β-lactamase inhibitors
Which penicillins have good oral availability?Penicillin V & Penicillinase Resistant Penicillin (Hard to resist the oral V)
What are Penicillinase Resistant penicillins effective against?Staph (penicillinase prod), Bacillus sp.
What are broad spectrum penicillins effective against?Microbes susceptible to natural penicllin, Enterobacteriaceae
What are extended spectrum penicllins effective against?Gram - aerobic and anaerobic microbes, Enterobacteriaceae (incld Pseudomonas sp), Bacteroides Fragilis


Question Answer
Are Cephalosporins resistant to β-lactamase?They are "more resistant"
What do 1st gen Cephalosporins treat?G+ (spec beta lactamase positive) & G- (1st gen=back to basics)
What are the important 1st gen Cephalosporins?Cefadroxil
Which 1st gen Cephalosporin is given parenterally for small animals and is the best at Tx? Tx what?Cefazolin, G-'s ("zolin!", the small animal parent called, a negative tone in her voice)
Which 1st gen Cephalosporin is given to treat mastitis?Cephapirin (Her breasts were covered by nothing but her aprin)
Which 1st gen Cephalosporin is given as ophthalmic ointment for bacterial conjunctivitis in dogs & cats?Cefalonium (think of Jimmy Falon's eyes)
(can also be given intramammary for mastitis in cattle)
What are the Important 2nd Gen Cephalosporins?Cefaclor
Cefuroxime (also in categ are cefamandole, cefonicid, and cefprozil)
What do 2nd gen Cephalosporins work against?G-s (better antibact action than 1st gen), aerobics (treating septic peritonitis)
Which 2nd gen Cephalosporin has CSF penetration?Cefuroxime (so furoious I punched into the spinal cavity & CSF leaked out)
What are the Cephamycin group 2nd gen Cephalosporins?Cefotetan (paranteral)
Cefoxitin (parenteral)
What two 2nd generation Cephalosporins are effective in tx of Bacteroides Fragilis?Cefoxitin and Cefotetan
What are the important 3rd generation cephalosporins?Cefixime
Cefpodoxime Proxetil
(aslos ceftizoxime and ceftriaxone)
Which 3rd gen Cephalosporin is painful & irritating to cats & dogs?Cefotaxime (this drug is taxing on dogs & cats)
Which 3rd gen cephalo has a very long half-life? How long?Cefovicin. 5 days in dogs, 7 days in cats (vices take a LONG TIME to break...esp if youre a cat like me)
Which cepha is given as a single SC injxn in dogs & cats for pyoderma/skin infxns?Cefovicin (the long acting 1) (the fast & easy way is a vice)
Which 3rd gen cephalo is a pro-drug ester?Cefpodoxime Proxetil (po in 1st word & pro in the other word)
Which 3rd gens are effective against pseudomonas?Cefoperazone, Ceftazidime (That pera owes me a lot of dime for giving me pseudomonas)
What 2 cephas are excreted mainly by bileCeftriaxone and Cefoperazone
Which 3rd gen has a metabolite (name it) just as active as the unmetabolized form?Ceftiofur → Desfuroylceftiofur (just as effective) (furry doggies are so active!!)
What are the various conditions of various species that Ceftiofur is used to treat? (4)(1) Resp infxns in cattle & pigs
(2) UTIs in dogs
(3) Pleuritis in horses
(4) E-coli in poultry
(FUR in your lungs, around your lungs, in your pee, & in your E-coli poop)
4th generation cephalosporins are more effective against _________________ and more resistant to _______________ than the other generationsResistant Infections, Beta lactamases
What are the wto 4th gen cephalos? What is its spectrum?Cefepime
broad spectrum (Gram + cocci, Gram - bacilli, and Pseudomonas Aeruginosa)
*Which 2 (3) cephalos are best against anaerobic infxns?Cefotetan & Cefoxitin (both are parenteral) (the fox tetan suffocated his enemies) (also Cephamycins)
Which cephas are effective against Bacteroides fragilis? What other property do they have?Cefoxitin & Cefotetan. More resistant to Cephalosporinases (the fox tetan named is strong & destroys fragile things)
Which cephas have high oral absorption?Cephalexin & Cefaclor (if you lex [licks] chlorine, it will absorb in your tongue)
Which cephas penetrate the BBB?Cefuroxime
(4 x's & 1 z pass the BBB))
What is the metabolism of the ceftios?Liver, to form deacetyl derivatives (so acetylation I think)
Which cepha has a metabolite w/ a longer half-life than the parent compound?Cefotaxime (dealing w/ tax makes my life feel 1/2x longer)
How are most cephos excreted?Kidney → glom filt & tubular secretion → urine
Which cephas decreases platelet aggregation?Cephalothin & Cefmetazole (your platelets are looking thin, met)
Which cepha can cause anemia & thrombocytopenia in dogs?Ceftiofur (their fur will be covered in blood!)

Other β-lactams

Question Answer
Are Carbapenems cidal or static?Cidal (β-lactams are all cidal. also getting hit by a car will kill you)
What is the spectrum of Carbapenems?Broad (you can go far in a car!)
What are the 2 Carbapenems we care about?Imipenem, Meropenem
What is important to note about Imipenem? (A carbapenem)Use as LAST RESORT, it is metabolized by renal Dehydropeptidase to create a NEPHROTOXIC metabolite, so it is ALWAYS administered w/ Cilastatin (a renal enzyme inhibitor) (I-M-I is S-O-S)
What is the adverse side effects of the carbapenems? (Imipenem, Meropenem)Seizures (having a seizure in the car is bad)
Why is Meropenem less harmful than Imipenem?Its more soluble, so there are less adverse effects (it's merely ~mero!)
What is the monobactam we care about?Aztreonam (can be used in penn. allergic PTx!)
What is the unique & useful trait about the monobactam Aztreonam?It has lower immunogenicity, so it can be used in PTx allergic to penicillins (Az safe az if it werent a penicillin)
Carbapenems used to treat what?Used for treating seriously resistant infxns
Which has the broadest spectrum of action?Imipenem (why it is used as last resort even tho it messes up your kidneys)
**Which drugs are OK for penicillin-sensitive patients?Carbapenems, Monobactams
**Which drugs are resistant to penicillinase enzymes?Cloxacillin

**Which β-lactam can kill pseudomonas?Carbapenicillin (RUN OVER PSEUDOMONAS IN YOUR CAR)
What must you give w/ Imipenem?Cilastatin