Antibiotics

cephalosporins

dihydro ring no thioz ring

how do cephalosporins kill

time dependent, and bactericidal

1st gen ceph

cefazolin

Cefazolin (g+) coverage

MSSA, staph +strep

cefazolin g- coverage

minimal, some e.colie and Kleb

cefazolin uses

surgical prophylactically, cellulitis and bacteremia

2nd gen cel

cefuroxime

cefuroxime coverage (g+)

less than 1st gen, strep pneumo and less g+ cocci

cefuroxime coverage (g-)

more than 1st gen, beta lactamase h.influenza, some e.coli

cefuroxime uses

outpatient UTI and respiratory infections

third gen cef

ceftriaxone and ceftazadime

ceftriaxone (g+ coverage)

less then 1 & 2 gen, meh on s. aureus, GREAT for strep pneumoniae 

ceftriaxone (g-) coverage

excellent against many Gram-negative bacteria, including E. coli and Kleb.

ceftriaxone does not cover

pseudomonas 

ceftriaxone uses

penetrates BBB very well, good for meningitis and community pneumonia, and UTI

Ceftriaxone Adverse Effects

complexes with Calcium and forms biliary sludge

Ceftazadime (g- coverage)

broad spectrum and PSEUDOMONAS

Ceftazadime (g+coverage)

NONE

ceftazadime uses

hospital acquired CNS infections

4th gen cef

cefepime

cefapime (g-) coverage

good including pseudomonas

cefapime (g+) coverage 

pretty good including s.pneumoniae

cefapime (g-) coverage

pretty good INCLUDING PSEUDOMONAS

What does cefapime not cover

MRSA and s. epi

cefapime use

hospital acquired strep pneumo and staph

adverse effects of Cefapime

neuro toxicity in renal patients

5th gen cef

ceftaroline

how should I think of ceftaroline

ceftriaxone plus MRSA

ceftaroline (g+) 

multi drug resistant G+, MRSA, S. pneumoniae

ceftaroline (g-) coverage

h.flu, e.coli, , kleb

what does ceftaroline not cover

pseudomonas

pb2a

how ceftaroline is able to combat MRSA

adverse effects of ceftaroline

autoimmune hemolytic anemia 

uses of ceftaroline

oral anaerobes, skin soft tissue infections, and community-acquired pneumonia

MonoBactam

Aztreonam

aztreonam coverage

no gram +, only gram negative and pseudomonas

what cephalosporin is aztreonam like 

ceftazidime

carbapenem

powerhouse beta lactam

carbapenem drug

imipenem/ciliastatin

imipenem coverage

broad g- and g+ but no MRSA

esbl

extended spectrum beta lactamases 

what does cilastatin do

It prevents the breakdown of imipenem in the kidneys, enhancing its antibacterial effectiveness.

imipenem good against which g -

pseudomonas, esbl, b.fragillis

imipenem adverse effects

decreases seizure thresehold like penicillin, renal concern

vancomycin mechanism 

binds to d-ala d-ala so PCBP cant come in 

Vanc mech of resistance

2nd d-ala turns into d-lactate and vanc can no longer bind but transpep still can

Vanc coverage

primarily gram + including MRSA and penicillin/ceph resistant s. pneumonia leading to meningitis, and eteroccous

adverse effects of vancomycin

infusion rxn that is histamine mediated, give Benadryl

Daptomycin mechanism of action 

disrupts the cell membrane with calcium on it and causes and efflux of potassium 

daptomycin mechanics of resistance

altering membrane potential, and decrease binding

daptomycin coverage

only gram positive, MRSA, VRE, Strep, coagulase - staph

daptomycin adverse effects

muscle toxicity

what is daptomycin not used for 

pneumonia and gram negative 

why do we use these

beta lactam resistant, or allergy, intracellular pathogens, lack cell wall

linezolid moa

50s

linezolid MOR

Rare

linezolid spectrum

Serious gram positive cocci, MRSA VRE

linezolid adverse effects

bone marrow suppression, serotonin syndrome

doxycycline moa

30s

doxy mor

target mod and efflux

doxy spectrum

CA acquired MRSA, S.pneumo, tick borne infections, chlamydia 

doxy adverse effects

yellow teeth, gi, photosensitive, esophageal irritation, metal interaction

Aminoglycos/gentamyin MOA

30s

gentamicin mor

enzyme inactivation, efflux pumps, target side modification

gentamicin spectrum 

serious gram -, sepsis

what can be used synergistically with beta lacatams

gentamicin

concentration dependent killing

gentamicin, need a higher concentration to reach the threshold then you get a post abx effect

gentamicin adverse effects

ototoxicity, nephrotoxicity (kidney and ears)

Macrolides MOA

50s

Macrolides MOR

Target mod and efflux

Erythromycin spectrum 

gram positive s.pneumo, s.aureous, atypical pneumonia 

adverse effects of erythromycin

qt prolong, inhibition of cyp450 3a, GI

Azithromycin Perls

less ddi, less gi, still has prolonged QT

Clarithromycin 

still has potential drug interactions, effective against some gram-positive bacteria and atypical pathogens.

Macrocyclic, fixdaxomicin MOA

Binds RNA Polymerase

fixdaxomicin mor

rare

fixdaxomicin use 

c.diff

clindamycin moa

50s

clindamycin mor

target efflux, ts modification, enzyme inactivation

clindamycin use

inhibits toxin production in staph and strep like TSS and Nec Fac

clindamycin spectrum

gram-positive and anaerobic bacteria and penicillin

clindamycin adverse effects

c. diff, rash GI

Quinolones MOA

Target DNA Gyrase and Topoisomerase

Quinolones MOR

Inactivating enzymes, prevent drug access, alter targets

Ciprofloxacin coverage

best for gram - pseudomonas, intra abdominal infections and UTI

Levofloxacin coverage

more gram +, less pseudomonas, more g+ for CA S.pneumo

moxifloxacin coverage

no pseudomonas, better g+ for CA s.pneumo and intra ab infections

fluoroquinolone adverse effects

QT Prolong, Tendon rupture, vitamins hinder absorption, renal precaution

TMP-SFX Mechanism

blocks enzymatic pathways and competes by mimicking PABA to inhibit bacterial folate synthesis.

Sulfa Mechanism of Resistance 

PABA over production, drug efflux, target enzyme 

Sulfa spectrum

Broad-spectrum against gram-positive and gram-negative bacteria.

is sulfa sensitive to MRSA

Some community acquired

sulfa is not used for 

group a strep

sulfa uses

mild mrsa/mssa, E.coli uti, PCP

Sulfa adverse effects

rash, bone marrow suppression,

Metronidazole MOA

Diffuses into cell and causes anaerobic damage with toxic intermediates in the ETC

Metronidazole MOR

NONE

Metronidazole spectrum

anaerobic bacteria and protozoa

metronidazole uses

intra abdominal and mixed bacterial infections

metronidazole adverse effects

GI, Neuropathy, metal taste, disusulferam rxn with alcohol