Tetracyclin

Question 1

Classification

Answer 1

1. Short acting: some hrs, 2/day
   Oxytetracycline, chlortetracycline, tetracycline.
   (intermediate:democlocyline - not in vet)
2. Long acting: 1/day Doxycycline, minocyline

Question 2

pharmacokinetics

Answer 2

Very lipophilic (BBB, IC bacteria), yellow discoloration of teeth in growing

Question 3

Mechanism of action

Answer 3

• Inhibitors of protein synthesis( 30S)
• Bacteriostatic
• at high conc. tetracycline can be concetrated in urine and become bactericidal (cell distruption of membrane)

Question 4

Spectrum

Answer 4

common resistance, anerobic and anaerobic

1. Mycoplasma: respiration tract infectio: sus, calves, poultry
2. IC: Rickettsia ,Chlamydophila , mycoplasma (anaemia,icterus), wolbachia ssp. (in symbiosis with dirofilaria imitis.
3. Borrelia, Anaplasma (WBCs, fever, lameness)
4. Bordetella bronchoseptica (kennel cough)

Question 5

1st choice?

Answer 5

Chlamydia (respiratory tracts,zoonosis), Borrelia, anaplasma (doxcy)

Question 6

Protozoa

Answer 6

Babesia spp. Plasmodium spp., Entamoeba histolytica , and Theileria spp.

Question 7

Resistance

Answer 7

1. Impaired uptake into bacteria - no uptake
2. Active efflux
3. Antibiotic degrading enzyme
4. Altering of the binding site of ribosomes

• Psuedomonas - ab ovo
• Acquired: due to widespread usage E.coli, Salmonella spp.
• Pasteurella multocida, Mannheimia haemolytica
• streptocci : 50%

Question 8

Pharmacokinetic

Answer 8

• Very high affinity to Ca+ Mg ions , penetrates the bone. DON’T give with dairy

Question 9

Pharmacokinetic

Answer 9

• Very high affinity to Ca+ Mg ions , penetrates the bone. DON’T give with dairy
  1. Classic: moderate absorption, low metabolism, urine excretions
  2. Long acting: excellent absorption, excretion in the large intestine, bile.

Question 10

Indications

Answer 10

Respiratory tract infection - (1st choice) , LYME Disease (6-8 W), Foot disease, UTI, Mastitis, metritis
*Proliferative eneropathy in eq (lawsonia) Doxycycline

Question 11

Side effects

Answer 11

very safe, esophagus irritation (give with food) , vomiting, diarrhea , dysbacteriosis, Rapid IV (collapse cuz Ca+ binding), tissue necrosis in parenteral, yellow discoloration of teeth in young and growing animals , hepato+nephrotoxicity , photosensitivity