B-Lactams Flashcards
B-Lactam Mechanism
Selectively interfere with bacterial cell wall synthesis
Categories B-Lactam
- Penicillins
- Cephalosporins
- Carbapenems
- Monobactam
Penicillins
- Bactericidal
- Penicillin G: Inactive against Gram (-)
- Interfere during transpeptidation; Inactivate PBPs
Four classes of Penicillins
Standard (G, V, + PK)
Antistaphylococcal (Nafcillin, Oxacillin, Dicloxacillin)
Extended-Spectrum (Amoxacillin/Ampicillin)
Antipseudomonal (Piperacillin)
Pen G
- Streptococci, enterococcus, P-susceptible pneumococci (Gram + Cocci)
- Neisseria (Meningococci) (Gram - Cocci)
Gram Positive Bacilli: Bacillus anthracis; Listeria Monocytogenes; Corynebacterium - Clostridium Perfringens
- Actinomyces Israeli
- Treponema Pallidum
- Leptospira
Pen V
- Oral Pen G
- Phayngitis, Scarlet Fever, URI
- Children
Benzthine Penicillin G
- B-Hemolytic streptococcal pharyngitis
- Sinusitis/Otitis due to strep/pneumococci
- Syphilis
Antistaph Pens General
- B-Lactamase staphylococci
- Serious systemic staph infections (endocarditis, meningitis)
Dicloxacillin
- Acid stable
- UTIs + RTIs
- 1 H before meals
Amoxicillin/Ampicilin
Anaerobes, enterococcus, susceptible gram (-) cocci, and bacilli:
- E. Coli, Proteus, Haemophilus influenzae, Moraxella, PAsteurella, Shigella, Salmonella, Campylobacter fetus
- NOT Klebsiella, Enterobacter, Pseudomonas, Citrobacter, Serratia, and other gram (-) aerobes
- UTIs, Sinusitis, Otitis Media, Lower RTIs
Piperacillin
- First Line Pseudomonas
- active against some gram (-) bacilli
- Combined with Taxobactom (Zosyn)
Mechanism of acquired Pen resistance
- Inactivation by B-Lactamase (Penicilinase)
- Decrease Permeability via efflux pump in Gram -
- Modification of Target PBPs (MRSA + resistant pneumococci)
Pencilling administration
IV/IM: PenG, Naf, Oxa
PO: PenV, Diclox, Amox, + Augmentin
Either: Ampicillin
G
Depot: Benzathine PenG
Pen Excretion
Renal Tubular excretion
Probenecid -> Inhibits tubular excretion + Prolongs
Nafcillin: Eliminated via biliary routes
AE penicillins
- Hypersensitivity
- Diahhrea
- Nephritis
- Neurotoxicity
- Platelet dysfunction
- Superinfections
Cephalosporin Generations affects
1: Gram Positive organisms
2-4: Improved activity against gram negative
5: Multidrug resistant Gram + Cocci
First Generation Cephalosporins
- Cephalexin, Cefazolin, Cefadrozil
- Gram + Cocci (Strep, Stap, pneum)
- Others: Proteus, E. Col, and Klebsiella
- NOT: MRSA, Enterococcus, Pseudomonas, aeuginosa, enters a term Serratus, citrobacter, bacteroides
- Oral: UTI, Pneum, Otitis Media, minor infections
- Parenteral: Surgical pretreatment, Bone + endocarditis
2nd Gen Cephalosorins
- Cefprozil, Cefuroxime, Cefaclor, Cefoxitin, Cefotetan
- Noncephmycins(NCM): Extended activity against Hem Inf, Moraxella Cat; NOT Serratia + Bacteroides
- Cephmycins(CM) (-Oxitin/-Otetan): Active against Bacteroides, C.Perf, Neis. Gon., and Serratia
- Clinical NCM: Oral for U/LRI; Skin infections; UTIs
- Clinical CM: Parenteral for Neis Gon.; Peritonitis/ diverticulitis
3rd Gen Cephalosporins names
Ceftriaxone Cefotaxime Ceftazidime Cefdinir Cefixime Ceftibuten Cefpodoxime Cefditoren
BBB 3rd Gen Ceph
Cephtriaxone
Cephotaxime
Ceftazidime
Cephtriaxone
- Gonorrhea, Chancroid, typhoid fever, Haemophilus meningitis, Pen-res Strep Pneum, Bacteremia, UTIs, RTIs, Bone infections, skin/ST infections
Cepftazidime
- Pseudomonas
- UTIs, Meningitis, Bacteremiam pneumonia
*W/ Avibactam for complicated UTIs, pyelonephritis, Intrabdominal for PTs Under 18 YO
Cefixime
1st line gonorrhea
Cefdinir
- Most common 3rd gen prescribed
- RTIs, Skin infections
- Pediatrics (Taste)
4th Generation (Cefepime)
- IV or IM
- INC resistance to chromosomal B-Lactamase (Enterobacter)
- Strep, Staph, Enterobacter, pseudomonas, Proteus, E. Coli, Klebsiella; HIGHLY against Haem., Mora, Neis, and PRPneumo/staph
5th Gen Ceph
Ceftaroline
- IV Prodrug
- Multidrug resistant Staph (MRSA, VRSA, VISA)
- Enterococcis, Pneumococci, Strep, PEcK, Haem, Mora, Enterobacter
CSF Ceph
4th: Ceftriaxone, Cefotaxime, Ceftazidime
5th: Cefepime
Bone Ceph
Cefazolin
Probenecid + Ceph
Inhibits tubular secretion of Cephs + Prolongs activity
Bile excreted Cephs
Ceftriaxone
AE Cephs
- Cross-allergenic w/ penicillins
- Cefotetan: Hypoprothrombopenia + Bleeding disorders; Disulfiram Rxn
Carbapenems/Monopenem names
Imipenem
Meropenem
Doripenem
Ertapenem
Monopenem: Aztreonam
Cabapenem General
- Imipeneem, Meropenem, + Doripenem: Broad spectrum for Gram +, Gream - rods and anaerobes; Resitant to most B-lactamases
- Ertapenem: NOT pseudomonas
- Empiric therapy; Enterobacter UTIs, RTIs, Pseudomonas,
Imipenem use
- Inactivated by renal dehydropeptidase
- Combined with cilastatin for use
Carbapenem AE
- Nausea, Vom, Diarrhea
- Seizures
- Pen Allergy
Aztreonam
- Gram - Rods: PSeudomonal UTIs, Serratia, Enterobacter, E.Coli, Klebsiella Pneum
- Other clinical: Respiraoty symptoms in CF
- NOT activa against Gram + bcacteria or Anaerobes
- NO PEN cross-allergy
- IV/IM/Inhalation
