Pharm 2 - Antimicrobials 5

drraythe's version from 2015-09-10 00:28


Chloramphenicol & Friends

Question Answer
Chloramphenicol is _________ spectrumBroad
Type of killing kinetic for Chloramphenicol?Type 2 (Time-Dependent) (think of 2 swimming in a pool of chlorine)
What are the 3 groups (molecular) of Chloramphenicols?(1) P-­nitrophenol
(2) Dichloroacetyl
(3) Alcoholic
Is Chloramphenicol static or cidal?Static
Microbial susceptibility of chlors?G-, G+, anaerobes, incld Mycoplasma, Rickettsia
**What is the MOA for Chloramphenicol?Binds to 50S unit & INHIBITS bacterial enzyme Peptidyl Transferase (inhibits peptide formation) (Chlorine denaturing that protein enzyme shit)
What happens since the mammalian mitochondrial ribosomes are similar to the bacterial ribosomes?Chloramphenicol can inhibit the mammalian mitochondrial protein synth & can suppress bone marrow
What shouldnt you give Chloramphenicol w/ & why?Macrolides/Lincosamides, bc sites of action are adjacent
(competitive means not working great)
How is the distribution of Chloramphenicol?Wide → can go into milk, eye, BBB, prostate, can treat CNS & resp. infxns
Chloram is a neutral compound, which means it is ___ solubleLipid
Whats up w/ rumiants & Chloram?It is inactivated by ruminal microorganisms (& not good for them)
Administrations of Chlorams?Oral, parenteral (succinate!) aka IM+IV, & also otic & ophthalmic preparations ( everything.)
What special areas can Chloramp? TX?Eye, Ear, CNS, Resp Tract
What can you do to make Chloramphenicol more palatable?Chloramphenicol palmitate = more palatable
How are Chloramphenicols metabolized? What indications might this have?Glucuronidation (liver), so cats metabolize slowly, as well as young animals & liver PTxs struggle (alcol goes thru ur liver)
What must you consider if you give Chloram orally?Given orally, it will ↓ glucose absorption, which can lead to diarrhea in calves (drinking pool water instead of sugar water will give calves diarrhea)
**What major caution is there about giving Chloramp. to certain animals?CANT GIVE TO FOOD ANIMALS, bc can cause aplastic anemia in humans that eat products from them
**Can Chloramp be used in food animals?NO (aplasic anemia in humans)
Can Thiamphenicol & Florfenicol be used in food animals?Yes
Thiamphenicol is ___ solubleH2O (swim in the water w/ your thighs)
How is Thiamphenicol metabolized? Excreted?It isnt, excreted unchanged (nothing seems to change these damn thighs of mine)
Which 50 will/wont induce (reversible) bone marrow toxicity? IF yes, WHY?Chloramp will (has paranitro group) but Thiamphenicol & Florfenicol CANT (dont have para nitro group)
Which 50 is most resistant to bacterial inactivation? How?Florfenicol, bc it has a F in its structure
What is the most potent of the Chloram. derivatives?Florfenicol, bc resists enzyme degradation, bc of the F in its structure (F'in strong!)
Which 50S is best for UTIs? Why?Florfenicol, bc it is excreted unchanged (so it's running through your bladder & urethra & killing stuff as it goes) (FLORA in the URETHRA, BEWARE!!)


Question Answer
Are Macrolides static or cidal?Static
Spectrum of Macrolides?Broad
**Mechanism of action for Macrolides?Inhibits bacterial protein synthesis (Reversibly binds to the 50S ribosomal subunit, Inhibits translocation of tRNA from the amino acid acceptor site, & Interferes w/ addition of new peptide bond) (MAC dated a TRANS girl)
What should you never administer w/ Macrolides?Chloramphenicol, or Lincosamides (for the 800th time..l)
Which 50S dont produce bone marrow suppression?Macrolides dont, neither do Thiamphenicol & Florfenicol. (Chloramphenicol DOES) (Only chlorine burns up your bones)
How can you enhance the effects of Macrolides?↑ pH to 8+ (Mac only likes girls who are an 8 or more)
What are the 6 Macrolides?Erythromycin
Clarithromycin (Mac... CAT TET)
Erythromycin (Macrolide) affects which bacteria?G+, campylobacter (pref drug for C. Jejuni), Rhodococcus equii (IF GIVEN W/ RIFAMPIN) (ERY dog has a positive attitude when CAMPing w/ horses)
**How is Erythromycin (Macrolide) administered? Anything to note about this?Orally, but can cause diarrhea in calves ** (due to the glucose malabsorbtion)& enteric coated to bypass acids in stomach (ERY calf got diarrhea when there was not a enteric coating)
How is Erythromycin (Macrolide) excreted?BILE, MILK, & URINE! (Erry b.u.m. excretes errywhere)
What bact are susceptible to Tilmicosin (Macrolide)?G- (Tilly was a negative lady)
What type of infxns are Tilmicosin (Macrolide) good against?Resp infxns (TY & TL & hitting & LUNGS, remember?) (& mycoplasma)
How is Tilmicosin (Macrolide) excreted?Urine & bile
Major consideration of risk of using Tilmicosin?CARDIOTOXICITY IF USED IV (inject me Til mi HEART STOPS)
**Major consideration of risk of using Tylosin (Macrolide)?TOXIC IN HORSES
What is a benefit of using Tylosin (Macrolide)?No enteric coating needed (Ty didnt sugar coat stuff)
What bact is Tylosin (Macrolide) good against?Mycoplasma (remember that Ty & Tim hit ERY lung, & MYCOPLASMA infects lungs often)
Killing kinetics of Azithromycin (Macrolide)?TYPE 3!!! (Time-Dependent & post antibiotic effect) (Aziz is 3x cooler than anyone I know)
Tiamulin (Macrolide) is good for treating what, & how is it then administered?Mycoplasma (pink eye) & can be admin in the feed (Tia the cow has pink eye)
Spectrum of Azithromycin? (Macrolide)Broad (Aziz has a broad shoulders)
How is Azithromycin (Macrolide) excreted?Via BILE (if you lie to Aziz he will spew bile in your face!)
What special affect does Azithromycin have? (Macrolide)Post-antibiotic effect (PAE) (The feeling you get when you hang out w/ Aziz lasts for 7-10 DAYS!)
How is Clarithromycin (Macrolide) excreted?URINE+BILE (Claire went to UB)
2 mechanisms of bacterial resistance against Macrolides?↑ efflux & ribosomal alteration (review also said inhibit liver enzymes, but idk where this is)
What drugs/concerns/things will you think about if I say "cross resistance"?CROSS-RESISTANCE BETWEEN MACROLIDES, LINCOSAMIDES & CHLORAMPHENICOL


Question Answer
Killing kinetics of Lincosamides?Type 2 → Time-Dependent (2 had a friend named LIN)
Lincosamides cidal or static?Static
What are Lincosamides effective against?G+, AEROBIC, MYCOPLASMA, but NOT G-s
What are the route(s) of admin for Lincosamides? Notes about it/them?ORAL → rapid but incomplete, FOOD IMPAIRS ABSORPTION. IM- rapid & complete (Lin’s muscles are better than her mouth)
Which 50S would you want to say "dont eat before taking this"?Lincosamides (Lin gets sick from eating & taking drugs)
Which Lincosamide isnt affected by if you eat food?Clindamycin (I could give this to rollie whenever)
Lincosamides reach high tissue conc. bc they are _________, & can reach the (which places?)Lipid soluble, respiratory secretions, soft tissue, prostate, bones & joints
Which Lincosamide can cross the placental barrier & attains high conc in the brain?Clindamycin (Linda has drugs on the brain)
How are Lincosamides metabolized?Not metabolized (Lin is fat, she has no metabolism)

Check yo'self before you wreck yo'self

Question Answer
How is the oral absorption of Clindamycin?High
What bact can Clindamycin be effective against?G- anaerobes (Linda hates that negative G named Ana)
**What drug is effective against Toxoplasma Gondii?CLINDAMYCIN (when rollie took this, it must have cleared out any potential toxo he had)
Lincosamides are excreted in the?Bile & urine (LIN says BI to U)
Resistance mechanisms of bacteria against Lincosamides?Efflux & Ribosomal Alteration
Adverse effects of Lincosamides & in who?Loose stool (dogs), vomiting (cats), DONT USE ORALLY IN Chinchillas, guinea pigs, hamsters, horses, ponies & rabbits. (screws up the GI flora) (Lin one way, out the other, & rodents/hind gutters are just screwed if oral)
Which animals are more sensitive to Chloramp toxicity?Young animals, cats, animals w/ impaired liver function → more sensitive for toxicity (young = liver isnt the best. liver impaired = liver isnt the best. Cats = big surprise there)
Which of the 50S is less sensitive to enzyme inactivation?Florfenicol (FLORish even w/ those nasty inactivating enzymes)
What treats cattle & pigs for respiratory diseases & has a long half-life?The Macrolide Tulathromycin (tulip the cow/pig is sniffing the flowers)
Does not interfere mammalian mitochondrial protein synthesis is... (& who does?)Doesnt = Macrolides
Does = Chloramph
ERYTHROMYCIN kills what bact that she emphasized?Campylobacter in cats & dogs (ERY dog loves to CAMP)
TILMCOSIN kills what bacteria she emphasized?Mycoplasma
What is MOST POTENT against mycoplasma?Tylosin (Ty is totally beating up those lungs)
Which drugs get the highest conc in lungs (So good for resp infxns)?Erythromycin, Tylosin, Tilmicosin (TY hit ERY LUNG TIL it was DEAD)
**DONT GIVE HORSES _________Tylosin
Why should you be careful administering Macrolides w/ other drugs? (Not talking about cross reactivity here)They inhibit CYP450 (↓ metabolism of other drugs) (mac will miss w/ your liver, man!)
Which Macrolides are Type 3, when usually it should be Type 2?Tulathromycin, Azithromycin
Which Lincosamide attains high conc in the brain?Clindamycin (Linda got drugs on the brain)
**Tox of Tilmicosin?Cardiotoxicity (horses) (TIL THEIR HEART DIES)
**Tox of Lincomycin?Hind gut fermented = fatal enterocolitis – will ↑ E.coli, opportunistic pathogens (Lin a horse, Lin will kill)
Which type of cows do you use Florfenicol on?More likely beef than dairy
To Tx H. pylori?Clarithromycin (Claire has an ulcer shes gonna get fixed)
Dont give Clindamycin to who?Chinchillas & shit