Bacteriostatic inhibitors of bacterial protein synthesis: tetracyclines, macrolides, clindamycin, linezolid Flashcards
Which drug classes are bacteriostatic inhibitors of bacterial protein synthesis (4)
1) tetracyclines
2) macrolides
3) clindamycin
4) linezolid
Common Uses of tetracyclines
1) doxycycline- MRSA, PNEUMONIA, CELLULITIS
2) tetracycline, minocycline- acne
- gram +, gram -, MSSA, atypicals
- doxycycline does MRSA
MOA of tetracycline
inhibits bacterial protein synthesis
ADR of tetracycline
1) tooth mottling- avoid kids
2) GI irritation
3) photosensitivity
available tetracyclines (3)
1) tetracycline
2) doxycycline (vibramycin, monodox)
3) minocycline (minocin, solodyn)
metabolism/ excretion of tetracyclines
significant absorption chelation can occur and prevents absorption with positive cations ( absorption issues with cations)
- SIMILAR TO WITH FLUOROQUINOLONES
3 main macrolides and route of administration
1) azithromycin - oral and IV
2) erythromycin - oral, iv and topical
3) clarithromycin - oral
Common uses of macrolides
- gram + and gram - but NO MRSA OR PSEUDOMONAS COVERAGE
1) azithromycin- upper respiratory infections, pneumonia, COPD exacerbation
2) ezithromycin - acne,
3) clarithromycin- not used often - gram+, gram -, atypicals, MSSA
similar to cefuroxime + atypicals
MOA of macrolides
inhibits bacterial protein synthesis
ADR of macrolides
azthromycin- QT prolongation (increased risk of fatal heart rhythms
metabolism/ excretion of macrolides
- significant drugs interactions.
CLARITHROMYCIN IS A STRONG CYP 3A4 INHIBITOR (many drug interactions)
Clindamycin Uses
1) Gram + and some anaerobes ( like for a aspiration pneumonia or dental abscess)
2) MRSA through the “D test”
3) NO GRAM - coverage ( may warrant double coverage if suspect multi resistant organisms)
- MRSA, MSSA, Gram +, anaerobes
Black box warning clindamycin
C. diff colitis
- worry the most about this the most with clindamycin and c.diff, so we don’t use it much in outpatient settings
What is a d-test
Checks for susceptible resistance
positive test: blunted effect and has some resistance
MOA of clindamycin
inhibits bacterial protein synthesis
Routes clindamycin
600 -900 mg for IV dosing (high)
350-400 mg BID (oral)
- iv doses tolerated better ( and bigger dose IV than oral)
ADR of Clindamycin
- AAD (antibiotic associated diarrhea)
- Cdiff
Metabolism/excretion clindamycin
no heptaic or renal adjustment
linezolid (zyvox) uses
1) GRAM + ONLY (like clindamycin)
2) NO anaerobes or Gram 3) MRSA infections, VRE- pneumonia and cellulitis
- RESTRICTED USE IN MOST INSTITUTIONS
- VRE, MRSA, MSSA, GRAM +
Linezolid (zyvox) moa
inhibit bacterial protein synthesis
contradicitions to linezolid
concurrent use or within 2 weeks of monoamine oxidase inhibitors (mAOIs)
linezolid (zyvox)
IV or Oral tabs
ADR Linzeolid
diarrhea
Metabolism/excretion of Linezolid
1) acts as an MAOI- increased risk of serotonin syndrome in combination with SSRI or SNRI
