Protein synthesis inhibs-Antimicrobials Flashcards
70 S ribosomes made up of a 30 s subunit and a 50 S subunit are found in?
Prokaryotes
*80 S with 40 s and 60 S subunits in Eukaryotes
High doses of drugs that interfere with protein synthesis can also interfere with what human component?
Human Mitochondria (closely resemble bacterial ribosomes)
Gentamycin, amikacin, tobramycin, streptomycin and neomycin are all what type of protein synthesis inhibitor?
Aminoglycosides
Tetracyline, doxycycline, minocycline, and tigecycline are all what type of protein synthesis inhibitor?
Tetracyclines
Erythromycin, clarithromycin and azithromycin are all what type of protein synthesis inhibitor?
Macrolides
Though they do not fall into a specific category, chloramphenicol, clindamycin, linezolid quiniprositin/dalfopristin and mupirocin are what type of drugs?
Protein synthesis inhibitors
What type of drugs bind the 30 S ribosomal subunit to block initiation, prematurely terminate, and cause misreads in translation?
Aminoglycosides
Having a post-antibiotic effect and bactericidal properties, aminoglycosides are given through IV of IM (not oral) to combat what type of organisms?
Severe Aerobic gram (-) (ie. Pseudomonas aeroginosa)
*Neomycin is used topically because of nephrotoxicity
What are some side effects of aminoglycosides?
- ototoxicity (destroys hair cells)
- Nephrotoxicity (need to monitor plasma concentrations)
- teratogen
What are the 5 main aminoglycosides and their administration?
1-Streptomycin (IM/IV, high resistance to this)
2-Gentamycin (IV, most commonly used)
3-Amikacin (IM/IV, broadest spectrum)
4-Tobramycin (IM/IV, pseudomonas aeruginosa)
5-Neomycin (topical, can be enema to detoxify colon)
Which drug type is bacteriostatic, broad spectrum (G (+/-)), binds the 30 s subunit, has cross resistant within group, and is 1st choice drug for rickettsial, mycoplasma, chlamydial, brucellosis, cholera, lyme disease and plague?
Tetracyclines
*also used as 2nd choice for mixed respiratory infections
What are some adverse effects of tetracyclines?
1-Hairy tongue
2-Teeth staining
3-headache
4-metallic taste
*avoid with alcohol
Tigecycline has the same spectrum as other TTCs plus what?
MRSA, multidrug resistant S. pneumonieae, vancomycin resistant enterococci and some anaerobes
Among the safest of antibiotics, which group of broad spectrum, 50 s binding antibiotics are bacteriostatic and used as 2nd line for skin and soft tissue not due to MRSA?
Macrolides (ketolides)
Why are macrolides dangerous in the liver?
all but azithromycin inhibit CYP450 which can cause accumulation of drugs metabolized by these enzymes.
*azithro has longest half-life
What drug is bacteriostatic in broad spectrum but bacteriocidal to H. influenza, and may cause hemolytic anemia, aplastic anemia, or gray baby syndrome?
Chlorpamphenicol
Affective against Gram (+) cocci, which drug may lead to pseudomembranous colitis and is antagonistic if co-administered with macrolides?
Clindamycin
Bactericidal agains streptococci and bacteriostatic agains enterococci and staphylococci, which drug is generally well tolerated but may cause serotonin syndrome in patients taking SSRIs?
Linezolid
Used only for serious infections of multi drug resistant gram (+) organisms, which drug binds 50 s subunit and does not need dose adjustment in renal insufficiency?
Quinuprostin/Dalfopristin (30:70 ratio) (Streptogramins)
Which drug is unique in that it reversible inhibits transfer-RNA synthetase enzyme and is bactericidal?
Mupirocin (bactroban)
*often used topically
Which two classes of drug bind the 30s subunit?
Aminoglycosides and Tetracyclines
Which 5 drugs/categories bind the 50s subunit?
1-Chloramphenicol 2-Clindamycin 3-Macrolides 4-Linezolid 5-streptogramins
Mneumonic for Aminoglycosides?
MEAN (amine) GNATS canNOT kill anaerobes
mneumonic for tetracyclines?
VACUUM THe BedRoom
Which drugs/groups are bacteriostatic?
- Tetracyclines
- Chloramphenicol
- Macrolides
- Linezolid
- Streptogramins
Which drugs/groups are bactericidal?
- Mupirocin
- Aminoglycosides
