Beta Lactam Antibiotics Flashcards
Natural Penicillins
Penicillin VK
Penicillin G Benzathine (Bicillin L-A)
Activity:
- Streptococci
- Enterococci
- Gram - anaerobes (mouth flora)
PenG: DO NOT GIVE IV
Antistaphylococcal Penicillins
Dicloxacillin
Nafcillin
Oxacillin
Activity:
- Streptococci
- Staphylococci (inc MSSA)
Notes:
- preferred for MSSA soft tissue, bone, joint, endocarditis, & bloodstream infections
- no renal adjustments
- Nafcillin is a vesicant -> extravasation treatment: cold packs & hyaluronidase injections
Aminopenicillins
Amoxicillin
Ampicillin
Activity:
Streptococci
Enterococci
Gram + anaerobes (mouth flora)
Some gram -
- Haemophilus
- Neisseria
- Proteus
- E coli
Notes:
- Amoxicillin: do not use XR forms if CrCl < 30
- Ampicillin PO rarely used dt poor F
- IV ampicillin must be diluted in NS only
Aminopenicillins + beta-lactamase inhibitor
Amoxicillin/Clavulanate (Augmentin)
Ampicillin/Sulbactam (Unasyn)
Activity:
Aminopenicillin activity PLUS:
- MSSA
- More resistant G- (HNPEK)
- Gram - anaerobes (B. frag)
Notes:
- Do not use Augmentin XR formulations if CrCl < 30
- IV Unasyn must be diluted in NS only
HNPEK
More resistant gram negatives:
- Haemophilus
- Neisseria
- Proteus
- E coli
- Klebsiella
Extended spectrum penicillins
Piperacillin/Tazobactam (Zosyn)
Activity:
Broad spectrum activity
Cover same as Amino + BLi PLUS
Other gram negatives: Citrobacter, Acinetobacter, Providencia, Enterobacter, Serratia (CAPES), and PSEUDOMONAS
Penicillin class characteristics
CI:
- type 1 HSR to another beta-lactam
ADE:
- seizures (with accumulation due to incorrect dose)
- GI upset
- diarrhea
- rash (inc SJS/TEN/HSR)
- hemolytic anemia
- renal failure
Monitor:
- renal function, sx of HSR w/ 1st dose
Penicillin DDIs
- Probenecid can inc levels of beta lactams (sometimes used on purpose)
- inc levels of methotrexate
- Most beta-lactams enhance anticoag effect of warfarin
- Exception: Nafcillin & Dicloxacillin inhibit the anticoag effect of warfarin
1st gen cephalosporins
Cefazolin
Cephalexin (Keflex)
Activity
- Gram positive cocci (strep & staph)
- Some activity against gram negative rods (proteus, E coli, klebsiella (PEK))
2nd gen cephalosporins
Cefuroxime
Cefotetan (Cefotan)
Cefoxitin
Cefuroxime:
- Staph
- More resistant strains of S pneumoniae
- HNPEK
Cefotetan, cefoxitin:
- Same as above + gram negative anaerobes (B fragilis)
3rd gen cephalosporins
Cefdinir
Ceftriaxone
Cefotaxime
Ceftazidime (Fortaz, Tazicef)
Ceftriaxone, cefotaxime, cefpodoxime, cefdinir:
- Resistant strep (S pneumoniae & viridans)
- Staphylococci (MSSA)
- Gram positive anaerobes (B fragilis)
- Resistant strains of HNPEK
Ceftazidime:
- Lacks gram positive activity
Covers pseudomonas
4th gen cephalosporins
Cefepime
Broad gram negative activity:
- HNPEK
- CAPES (Citrobacter, Acinetobacter, Providencia, Enterobacter, Serratia)
- Pseudomonas
Gram positive activity:
- Resistant strep (S pneumoniae & viridans)
- Staphylococci (MSSA)
- Gram positive anaerobes (B fragilis)
5th gen cephalosporins
Ceftaroline fosamil (Teflaro)
Activity:
- Broad gram negative & gram positive activity
- The only cephalosporin that covers MRSA
Cephalosporin CI
- Hyperbilirubinemic neonates (causes biliary sludging & kernicterus)
- concurrent use with calcium containing IV products in neonates < 28 days old
Cephalosporin Warnings
Cross reactivity with penicillin allergy
Cephalosporin ADE
seizures with accumulation (incorrect dosing)
GI upset
diarrhea
rash/allergic rxns/anaphylaxis
hemolytic anemia
SJS/TEN
Cefazolin
1st gen cephalosporin
IV/IM
Keflex
1st gen cephalosporin
Cephalexin
PO
Common uses:
- skin infections (MSSA)
- strep throat
Cefuroxime
2nd gen cephalosporin
PO/IV/IM
Common uses:
- acute otitis media
- CAP
Cefotan
2nd gen cephalosporin
Cefotetan
IV/IM
contains a side chain with can increase risk of bleeding & cause a disulfiram-like reaction with alcohol ingestion
Cefoxitin
2nd gen cephalosporin
IV/IM
Cefdinir
3rd gen cephalosporin
PO
Common uses:
- acute otitis media
Ceftriaxone
3rd gen cephalosporin
IV/IM
no renal adjustment
CNS penetration with high doses (e.g. 2g Q12H)
Cefotaxime
3rd gen cephalosporin
IV/IM
Fortaz, Tazicef
3rd gen cephalosporin
Ceftazidime
IV/IM
Cefepime
4th gen cephalosporin
IV/IM
Teflaro
5th gen cephalosporin
Cetaroline fosamil
IV
Cephalosporin DDI
calcium containing IV fluids -> precipitate
Cefuroxime, cefpodoxime, & cefdinir should be separated from antacids by 2 hrs
Merrem
Meropenem
Class: carbapenem
Invanz
Ertapenem
Class: carbapenem
commonly used for diabetic foot infections
Carbapenem clinical characteristics
CI: beta lactam allergy
Warnings:
- do not use with penicillin allergy
ADE:
- diarrhea, rash/severe skin rxn, bone marrow suppression with prolonged use
- CNS effects (AMS, seizures) with larger doses or renal dysfunction
Monitor:
- renal function
Carbapenem activity
Very broad spectrum, usually reserved for MDR gram negative infections
Easier to list what they don’t cover:
- atypical pathogens
- MRSA
- VRE (vanco resistant enterococci)
- C diff
Ertapenem has no activity against pseudomonas, acinetobacter, or enterococcus
Azactam
Aztreonam
Class: monobactam
Can be used in pts with beta lactam allergy
Activity:
- good gram negative coverage (HNPEK, CAPES, pseudomonas)
- no gram positive or anaerobic activity
