Antibiotics 1

1. SULFONAMIDE

   Anotações:

   • Synergy with trimethoprim leads to bacteriocidal effect
   1. Competitively inhibits dihydropteroate synthetase
   2. Pregnancy, nephrotox, hemolysis

      Anotações:

      • Cross placenta
2. TRIMETHOPRIM

   Anotações:

   • Synergy with sulfonamide often make bacteriocidal effect
   1. Inhibits dihydrofolate reductase
3. Bacteriostatic

1. PENICILLINS, CEPHALOSPORINS
   1. Block transpeptidase rxn

      Anotações:

      • by binding penicillin binding proteins
   2. Very safe!

      Anotações:

      • We don't have these proteins in our cell walls
   3. Penicillin G - neurotox

      Anotações:

      • From non-specific irritation
   4. Least toxic, most allergenic
2. VANCOMYCIN, BACITRACIN
   1. Block early steps in synthesis
   2. Toxic to kidneys
3. CYCLOSERINE
   1. Blocks alanine racemase

1. POLYMYXINS
   1. Form pores
   2. Bind phosphatidyl ethanolamine-rich areas of membrane
   3. Highly toxic to kidneys

      Anotações:

      • We have phosphatidyl ethanolamine in our membranes Why these are toxic
   4. CHOLISTINS

      Anotações:

      • Currently being made

1. Aminoglycosides
   1. Bind to 30S
   2. Bacteriocidal
   3. STREPTOMYCIN
      1. Pregnancy

         Anotações:

         • 8th cranial nerve damage Skeletal defects
   4. Nephrotox, neurotox

      Anotações:

      • Neurotox in infants
2. TETRACYCLINES
   1. Blocks tRNA binding 30S
   2. Bacteriostatic
   3. Pregnancy, liver tox, neurotox

      Anotações:

      • Hypoplasia of fetal teeth & bones in fetus Cataracts in fetus Neurotox in infants
3. CHLORAMPHENICOL, ERYTHROMYCIN, CLINDAMYCIN
   1. Bind 50S
   2. Inhibit chain elongation
   3. CHLOR - pregnancy, inhibits P450, toxic to marrow/hemolysis

      Anotações:

      • Crosses placenta
   4. CHLOR - phenytoin, coumadin

      Anotações:

      • Inhibits their breakdown

1. RIFAMPIN
   1. Inhibits DNA-dependent RNA polymerase
      1. Inhibits RNA synthesis
   2. Birth control pills

      Anotações:

      • Enhances breakdown
2. Quinolones
   1. CIPROFLOXACIN
      1. Blocks DNA gyrase
3. METRONIDAZOLE
   1. Inhibits nucleic acid synthesis

1. GOOD
   1. Sulfonamide + trimethoprim
   2. Isoniazid + rifampin
      1. Treat TB
   3. Penicillin + aminoglycoside

      Anotações:

      • Penicillin stops cell wall formation Allows aminoglycosides to get inside
      1. Mixed infections
      2. Prophylaxis
   4. Trimethoprim + sulfamethoxazole
      1. Treat Pneumocystis carinii pneumonia

         Anotações:

         • In people with AIDS
   5. Bactericidal + bactericidal or bacteriostatic + bacteriostatic
2. BAD
   1. Bactericidal + bacteriostatic
   2. Penicillin + tetracycline

1. GI

   Anotações:

   • C. diff -> fatal colitis Nausea & vomiting
2. Liver tox
   1. Isoniazid

Anotações:

• Antibiotics act as haptens (give immune response when attached to large molecule)