Macrolide; Inhibits protein synth.

Use: DOC for Legionella pneumophila pneumonia; Alternative to penicillin; abx; Mycoplasma pneumoniae, Chlamydia; Staph infection, otitis media, meningitis

Mechanism: reversibly binds 50 S subunit interfereing with initiation complex

Drug interactions: Chloramphenicol and erythromycin antagonize eachother (binding sites are close); inhibits hepatic metabolism (p405) of other drugs, increasin serum concentration

Resistance Mech: 1) ribosomal protection via methylase enzymes (Expression of ermA, ermB, ermC, which modify ribosomal target and decrease dx binding) cross resistance within the group; 2) Active pump; 3) hydrolysis by esterases; 4) 50 S subunit alteration

PHK: gastric acid destroys erythromycin; 

Spectrum: gram-positive cocci including many strains of Listeria, Staphylococcus aureus, Streptococcus pyogenes, S. pneumoniae, the viridans, streptococci and many strains of S. faecalis. ; Gram + bacilli; Mycoplasma pneumoniae, chlamydia, legionella pneumophila; Gram - organisms are resistant 

Tox: GI, diarrhea (motilin r stim.), elevates hepatic enzymes/cholestatic jaundice, ototoxicity, phlebitis, QT prolongation, torsade de pointes

Macrolide; Inhibitor of Protein Synthesis

Use: H. pylori durodenal ulcer, community acquired pneumonia; Alternative to penicillin; abx

Mechanism: reversibly binds 50 S subunit interfereing with initiation complex; penetrates lung tissue better than eryhtromycin so better against mycobacterium avium complex (MAC)

Spectrum: Moraxella catarrhalis, Mycoplasma pneumoniae, Legionella species, Chlamydia pneumoniae, Mycobacterium avium

Macrolide: Inhibits protein synth.

Use: Chlamydia, gonorrhea (combo with ceftriaxone); pediatric otitis media, pharygnitis, mycobacerium avium complex (MAC) prophylaxis; Alternative to penicillin; abx

Mechanism: reversibly binds 50 S subunit interfereing with initiation complex; penetrates lung tissue better than eryhtromycin so better against mycobacterium avium complex (MAC)

PHK: can be 1 daily; elimination largely in feces; IV available

NOT METABOLIZED IN LIVER, less drug interaction

Spectrum: Streptococcus viridans group, campylobacter jejuni, legionella pneumophila, Mycoplasma pneumoniae, Treponema pallidum *Borrelia burgdorferi (Lyme disease) - off label

Ketolide: Broad spec abx; Inhibits Protein Synth.

Use: respiratory pathogens that are erythromycin/penicillin resistant pneumococci; intracellular and atypical bacteria

Mechanism: binds 50S rubunit

PHK: CYP3A4, T1/2 9-10 hrs

Tox: Diarrhea

BLACK BOX: ;SERIOUS HEPATOTOXICITY

Inhibits protein synthesis

Use: Toxoplasmic encphalitis (combo with pyrimethamine)

Mechanism: Binds 50S ribosomal subunits, inhibiting protein synthesis

Spectrum: wide range of gram + cocci, several anaerobic gram - and gram + organisms; Streptococci, staphylococci, anaerobes (gram+/-)

PHK: high concentration in bone

Tox: Pseudomembranous colitis

Streptogramin: Inhibits protein synth.

Mechanism: blocks ribosome function by binding 70S or 50S particles

PHK: IV infusion

Tox: inhibit CYP 450 3A4

When administered together these abx act synergistically

Spectrum: vancomycin-resistant Enterococcus faecium bacteremia, complicated skin and skin-structure infections from S. aureus

Oxazolidinone; Inhibits protein synth.

Use: bacterial pneumonia, skin/skin structure infections, vanco resistant enterococcal infections (VRE); MRSA

Mechanism: binds 23s and 50s subunits (prevents 70s formation)reversible, non-selective inhibitor of monoamine oxidase (MAO)

100% oral bioavailability; does NOT involve hepatic microsomal oxidative system

Adverse reactions: MAOI adverse rxns