intiation

aa incorportation

peptide bond formation

translocation

aminoglycosides act at the initiation step

tetracyclines act at the amino acid incorporation step

chloramphenical block peptide bond formation

macrolides and clindamycin inhibit translocation step

they bind the 30s and cause misreading of bacterial DNA -> bactericidal

block the formation of mRNA

they ar etaken into the cells via and O2-dependent mech, so can't use w/ anaerobes

these are like sugars, so they are polar.

they are not absorbed orally, they are excreted by the kidneys.

since they are excreted by the kidneys, you need to adjust the dose in renal failure.

nephrotoxicity (6-7% incidence)

ototoxicity (2% incidence)

weird side effet = neuromuscular blockade, so don't give with muscle relaxants

gram - rods

streptomycin used in TB, DOC for bubonic plague and tularemia

they inhibit amino-acid incorporation by blocking the attachment of tRNA to the acceptor (A) site.

no, are bacteriostatic.

ar ebroad spectrum antibiotics that can be used against chlamydia, mycoplasma, h pylori, rickettsia, borrelia, brucella, and vibrio

it is lipid soluble and more effective than tetracycline. unlike the other tetra's is metabolize din liver (lipid sol)

useful for rickettsia and borrelia (DOC)

concentrates in prostate, so good for prostatitis (gonorrhea or chlamydia)

tooth enamel dysplasia

decreased bone growth in kids

phototoxicity (esp doxy)

NVD

superinfections -> candidiasis or colitis

vestibular dys w minocycline

contraindicated in pregnancy and children

kidneys!

except doxycycline, which is lipid sol and eliminated by the liver

since tetracyclines are known to interact with tooth enamel and bone growth, it makes sense that they interact with divalent cations (esp Ca2+).

Knowing this, what would you want to avoid doing when you take these?

eating, esp anything with lots of Ca2+, or taking antacids.

these drugs make pt's feel ill, so the tendency is to eat something with them...but this will decrease the absorption

the peptide bond formation step by inhibiting the activity of peptidyltransferase

is bacteriostatic

that the drug is lipid soluble, crosses BBB, and is met by the liver.

wide-spectrum

used as backup drug mostly

do get into the CNS, so can be used for sepsis and meningitis

gray baby syndrome: babies have less glucuronosyl transferase, so the drug can saturate this sys -> displacement of bilirubin and kernicterus in infants.

dose-dependent bone marrow suppression common

the translocation step.

they inhibit the translocation of tRNA form A site to the P site

are bacteriostatic

gram +  cocci

aypical organims (chlamydia, mycoplasma, and ureaplasma)

Legionella pneumophila

camplylobacter jejuni

respiratory infections

Azithromycin Air

kidneys, v the rest of the macrolides, which are metabolized by the liver and excreted in bile.

these also inhibit cytochrome P450's

(azithro does not)

and can cross the placenta (not safe in pregnancy)

azithro doesn't and so is safer in pregnancy

directly stimulate motilin receptors -> NVD

(used to prevent gut stasis after surgery)

cause reversible deafness at high doses

erythromycin can cause jaundice and cholestasis

osteomyelitis caused by G+ cocci (s aureus)

"clings to bones)

in healthy people, s aureus

iv drug users and diabetics, p aeruginosa

sickle cell patients, salmonella

clindamycin not useful for last 2, would use quinolones