IV ONLY

Use: resistant aerobic/anaerobic G+/G-

Assoc w/ FATAL BLOOD DYSCRACIA

Mechanism: inhibits aminoacyl-tRNA binding to acceptor site (problem: inhibits human mito peptidyltransferase); inhibits cytochrome P450

• Gray Baby Syndrome caused by:
  • insufficient glycoronyl transferase --> can't conj drug
  • underdev renal function --> can't eliminate

• INC Rx levels w/mito ribosomes
  • Dep respiration
  • CV collapse
  • Cyanosis (gray/blue skin)

Streptogramins, synergistic

MRSA & vancymycin resistant infections

CIDAL

IV ONLY, rarely used

Mechanism:

• Quinu - releases peptidyl-tRNA fr donor site
• Dalfo - inhibits binding of aminoacyl-tRNA to acceptor site & peptidyl-tRNA to donor site
• Inhibit CYP3A - DEC warfarin metabolism

• Arthralgias/mylagias
• Hyperbilirubinemia
• Superinfection --> colitis
• Venous irritation --> req catheter
• Vancomycin-res E. faecium

Uses:  E. faecium, MSSA, MRSA, other vancomycin-resistant infections

STATIC or CIDAL (dependn on microbe)

Oral & IV

Mechanism:  inhibits initiation complex formation

Run weekly CBC, do not use >28days

• Myelosuppression --> thrombocytopenia & colitis
• 5-HT syndrome when used w/drugs that enhance 5-HT activity
• Chronic use:
  • reversible optic neuropathy
  • irreversible peripheral neuropathy
  • lactic acidosis

Topical - acne

Suppository - bacterial vaginosis

Oral, IV

Mechanism:  inhibits translocation (A --> P site)

Other uses:  immunomodulatory activity, used w/PCN for grp A strep

• Pseudomembranous colitis (due to C. diff emergence)

• Uses:  G - bacteria

Common bacterial infections in conjunctiva and lids

Topical ONLY

Nephrotoxic and neurotoxic, caues neuromuscular block

Mechanism:  cidal cationic detergent (disrupts cell membrane)

Avail alone, or w/other Rx:

• Neosporin ointment - polymyxin B + gramicidin + neomycin
• Neosporin GU irrgant - polymyxin B + neomycin
• Polymyxin B + bacitracin

Colistimethate

aka Polymyxin E

G - rods

Mechanism:  cidal cationic detergent

Nephrotoxic and neurotoxic

IV/IM

Related to aminoglycosides

STATIC (not cidal like aminoglyc)

Use:  Single IM dose - gonorrhea in pt allergic to PCNs or PCN-resistant trains

Use:  traveler's diarrhea (fr noninvasive E. coli)

DEC risk hepatic encephalopathy in pts w/advanced liver disease

Rationale: DEC ammonia-producing bacteria

Mechanism:  binds DNA-dep RNA polymerase

• Flatulence (gas)
• Abd pain
• Urgency to defecate

Form:  Ointment & cream

Use:  IMPETIGO fr grp A strep or S. aureas

Mechanism:  inhibits bacterial isoleucyl tRNA synthetase

Use:  IMPETIGO

Form:  topical ointment

Mechanism:  blocks acceptor and donors sites of peptidyl transferase

1st Rx used in pleuromutilins class

Use:  G+/G- UTIs

Poor systemic levels - local action in tubules

Mechanism:  Reduced by urinary tract bacteria to reactive intermediates --> damages DNA, ribosomes, cell wall

• Caution: brown urine, do not use if Hx cholestatic jaundice or hepatic dysfunction --> hepatic necrosis, death
• Acute Sx:  fever, chills, cough, infiltrates (reversible)
• Chronic Sx (>6 mo):  malaise, DOE, cough, pneumonitis, fibrosis, etc

Uses:  G+, MRSA skin infections

NOT for penumonia bc inactivated by lung surfactant

Mechanism: creates pores in membrane --> K+ loss --> depol --> inhibits DNA, RNA & protein synthesis

Excreted unchanged by kidneys

• INC creatine kinase (CK)

IV

Use:  life-threatening P. falciparym (malaria)

Caution:  causes arrthymias

Uses: G+/G-, staph, MRSA, mycobacterium

Mechanism:  inhibits DNA-dep RNA pol

penetrates tissues, biofilm, lung cavities, abscesses

Use ONLY in combo w/other Rxs to prevent resistance

Excreted thru bile --> enterohepatic recirculation

• Do not give <2 wks -->flu-like Sx
• Red/orange urine, feces, saliva, sweat, tears (can stain soft contacts)
• Jaundice, fatalities rare
• Hepatitis rare

Enzyme inducer (ex. P450) - DEC dig, anticoags, contraceptives, etc.