Antibiotics 2 Flashcards
Antibiotics that inhibit protein synthesis
- tetracyclines
- macrolides
- Clindamycin
- aminoglycosides
Antibiotics that inhibit folate synthesis
sulfonamides
antibiotics that disrupt DNA replication/cell division
Fluroquinolones
Antibiotics that work by inhibiting nucleic acid synthesis
Metronidazole
Identifying tetracylcines
ends with “cycline”
adverse effects of tetracyline
- GI upset: nausea, vomiting, diarrhea
- cause C Diff
- photosensitivity
- yellow/brown discoloration of teeth
- superinfections
tetracyclines - w/ food or without?
food decrease GI upset BUT decreases absorption
-ideal w/o food
tetracycline and teeth
- do not give to children under 8/pre women
- -> tetracycline binds to calcium in developing teeth and is irreversible color change
Superinfection w/ tetracyclines
candidiasis, C Diff
tetracyclines food drug interaction
- Ca, Fe, Mg, Al – result in decrease drug absorption by 50%
- avoid anatacids, anti-diarrheal, dairy products
- take tetracyclines on empty stomach
macrolide function
inhibition of protein synthesis
macrolide prototype
erythromycin
identifying macrolides
end with “mycin”
ADR with erythromycin
- GI upset – increase GI motility
- can be used w/ diabetic gastroparesis or passing small bore feeding tubes into small instestine
beneficial use of GI upset of erythromycin
- GI upset – increase GI motility
- can be used w/ diabetic gastroparesis or passing small bore feeding tubes into small instestine
erythromycin drug drug interactions
- QT prolongation (Cardiac Death)
- CYP3A4 pathway (Ca channel blockers, antifungals, HIV protease inhibitors)
- Toxic levels w/ theophylline, carbamazepine, warfarin
Suprainfection
- C Diff
- Candidiasis
erythromycin dosing/route
- continuous infusion preferred over intermittent
- oral
Clindamycin fxn
inhibit protein synthesis
clindamycin and C Diff
- clindamycin can be fatal with C Diff
- if develop diarrhea on clindamycin, stop immediately
sxs of c diff
- profuse watery diarrhea
- abdominal pain
- fever
- leukocytosis
clindamycin infusion rate risks
(if give rapidly –> increase risk for cardiac death)
-IV,oral, topical
aminoglycosides fxn
inhibit protein synthesis by producing protein
- -> bacterialcidal
- BIG GUNS, stronger
aminoglycoside prototype
gentamicin
gentamicin links to
vancomycin
identifying aminoglycosides
ends with “mycin” or “Cin”
gentamicin route
IV or IM
gentamycin ADR otoxicity
- otoxicity - check trough levels
- tinnitus: affect cochlea
- vestibular area: headache 1st sign
- can be reversible, risk increase with high dose or long term use
gentamycin ADR
- ototoxicity
- nephrotoxicity
gentamycin nephrotoxicity + frequency
trough level check
- 5-25 % of patients
- labs: BUN/Creatinine/GFR
- usually reversible
- renal dose adjustment
sulfonamides fxn
inhibit folate synthesis
sulfonamide prototype
Trimethoprim/sulfamethoxazole
TMP/SMX
TMP/SMX ratio
1:5
TMP/SMX - together have _____ effect
synergist (1+1=3)
how does inhibition of folate synthesis work?
- all cells need folic acid to synth DNA/RNA/Protein
- only effects bacteria b/c bacteria are unable to take up folate and instead must synthesize it from precursors
- by inhibiting sythnesis of folate the bacterial cells die
- human cells can take up folate from the environment and do not need precursors
TMP/SMX prevalence and examples
common
-bactrim, cotrim
TMP/SMX adverse effects
GI, rash, blood dyscrasias , crystaluria, photophobia, CNS disorder, kernicterus, risk of hyperkalemia
TMP/SMX rash
- full body
- if rash develop stop to prevent Stevens Johnson Syndrome
TMP/SMX blood dyscrasias
- develop hemolytic anemia (G6PD)
- increase risk for preg/alcoholic to develop bone marrow suppression
TMP/SMX crystaluria
(can cause formation of crystals in urine)-
- prevent: by increase hydration to 8-10 glasses/day
- watch: BUN creatinine
TMP/SMX and CNS
-can cause headache, depression, hallucinations
TMP/SMX and pregnancy
- fetal development of kernicterus (jaundice)
risk: bilirubin is neurotoxic - do not use tmp/smx with preg, children <2 mo, breastfeeding
- take preg taste before taking
TMP/SMX allergy
-do not take if allergy to Sulfa drugs (thiazide diuretics, loop diurecic, Sulf DM meds)
TMP/SMX hypersensitivity
- steven johnson syndrome
- look like burn victim
- 25% mortality rate
TMP/SMX drug drug interactions
-warfarin, dilantin
fluroquinolones fxn
disrupt DNA replication/ cell division
Abx to infuse over 1 hr
- vancomycin
- ciprofloxacin
- metronidazole
fluroquinolones prototype
ciprofloxacin
identifying fluroquinolones
ends with “oxacin”
ciprofloxacin route
- oral
- IV - infuse over 1 hr
ciprofloxacin treats
uti, upper resp, anthrax
ciprofloxacin ADR
- GI upset
- CNS
- tendon rupture
- photosensitivity
- dysrhythmias
- superinfection (C diff, candidiasis)
ciprofloxacin tendon rupture, who is at risk?
- tell nurse if pain in back of heal
- highest risk = elderly + steroid use (COPD)
- avoid in kids under 18
ciprofloxacin cns
-dizziness, headache, confusion in elderly
ciprofloxacin dysrhythmias
-can cause if ALREADY on anti-dysrhythmia meds
ciprofloxacin drug food interaction
AL, Mg, Fe, Zinc, Ca
Milk/Dairy
-give drug 6 hours after or 2 hours before food
–> can reduce absorption by 90%
ciprofloxacin drug drug interactions
-sucrelfate, theophylline, warfarin, tinidazole
metronidazole fxn
inhibits nucleic acid synthesis
metronidazole works on what kind of bacteria
-only taken up by anaerobic bacteria/protozoa
-converted to active form
-causes bacteriacidal
NO action against aerobic bacteria
metronidazole treats conditions
C Diff
GI/Pelvic surgery
metronidazole route
- oral
- IV – infuse over 1 hr
metronidazole ADR
-gi upset
-superinfection (candidiasis)
-no alcohol for up to 3 days after
(research does not support disulfiram rxn)
-urine change to dark reddish brown
-metallic taste
