Short AB recap

Question 1

Prudent use of antibiotics

Answer 1

1. Only use ABs in case of confirmed bacterial infection
2. Select one narrow-spectrum AB specific
   to the agent
3. Only use broad-spectrum ABs if really
   needed
4. Treatment should be optimal length
5. Correct doses, correct administration
   intervals
6. Correct combination

Question 2

Beta-lactams

Answer 2

1. Contain beta-lactam ring
2. Inhibit bacterial cell wall synthesis
3. Most widely used ABs
4. Very low toxicity
5. Most common side-effect is allergic
   reaction
6. Penicillins; easily hydrolysed, oldest
7. Cephalosporins
   
   • 5 generations, 3-5 not recommended
     to be used in vetmed

Question 3

Gram+ antibiotics

Answer 3

Beta-lactam ABs like penicillins + Cephalosporins
- Very low toxicity, widely used
- Inhibit bacterial cell wall synthesis
Macrolides + Lincosamides
- More toxic than beta-lactams
- Used if there’s resistance to beta-lactams
- Inhibit bacterial protein synthesis

Question 4

Penicillins

Answer 4

1. Oldest antibiotic discovered - more than
   40 have been synthesised
2. Freely soluble, easily hydrolysed
3. Inhibit bacterial cell wall synthesis
4. Lowest level of toxicity among ABs
5. Most common side effect -allergy
6. Different groups:
   -Natural, Acid resistant
   
   • Penicillinase resistant
   • Broad spectrum penicillins
   • Aminopenicillins

Question 5

Macrolides, Lincomycin

Answer 5

1. Against G+ & G- bacteria, not beta-
   lactams
2. Inhibit bacterial protein synthesis
3. More toxic than beta-lactams
4. Used if there’s resistance to beta-lactams

Question 6

Macrolides

Answer 6

Largely excreted into bile and used in bile duct infections

Question 7

Lincomycin

Answer 7

Low toxicity to dogs and cats - very toxic to sheep, rabbits

Clindamycin is useful against toxoplasma gondii

Question 8

Gram- antibiotics

Answer 8

1. Aminoglycosides and Aminocyclitols
2. Inhibit microbial cell protein synthesis
3. Some effect against mycobacteria and
   mycoplasmas
4. Aminoglycosides
   
   • Very toxic, esps Neomycin
   • Accumulate in kidneys
   • Oto-, Nephro-, Neurotoxicity
   • Gentamycin

Question 9

Chloramphenicol, Tiamphenicol, Florfenicol

Answer 9

1. Broad spectrum, chemically similar
2. Inhibit microbial protein synthesis
3. Suppress metabolism of microbes

Question 10

Chloramphenicol

Answer 10

Most toxic antibiotic!!
Damages bone marrow, inhibits hematopoiesis -aplastic anemia
Only used in small animals topically
Increases potency of ketamine and barbiturates
Good for eye and ear infections
NEVER use in farm animals

Question 11

Tiamphenicol

Answer 11

Derivative of chloramphenicol
Lower activity, significantly less toxic

Question 12

Florfenicol

Answer 12

Derivative of tiamphenicol

Question 13

Tetracyclines

Answer 13

1. Broad spectrum
2. Inhibit microbial protein synthesis
   3.Accumulates in Ca-containing tissues
   - bones & teeth
   - Not recommended for young animals
3. If administered via IV, animal can
   collapse
4. Toxicity: kidney damage, liver damage,
   dehydration, Diarrhea, enterocolitis
   Hemoglobinuria

Question 14

Fluoroquinolones

Answer 14

1. Broad spectrum
2. Inhibits DNA synthesis of microbes
3. “reserve antibiotics”
4. Might cause joint cartilage erosions
   
   • Not for young animals
5. Vomiting, diarrhea, cramps
6. Enrofloxacin