C/12. Tetracyclines And Glycylcyclines

Question 1

Drugs need to know in this topic

Answer 1

Doxycycline

Tigecycline

Question 2

Tetracyclines

MOA

Answer 2

Binding to the 30S ribosomal subunit; inhibit binding ofr charged tRNA to the acceptor site
Bacteriostatic effect
Act as chelators; bind divalent cations (Ca2+, Mg2+..), which decrease their absorption
Accumulation in bone and teeth (due to the high Ca2+ content)

Question 3

Doxycycline

Answer 3

Alternative tx to macrolides in community-acquired pneumonia
Gonorrhea, chlamydia
Zoonotic diseases

Excreted in feces
Safe to use in renal dysfunction

Resistance mechanism
Efflux pump
Alternation of ribosomal binding site
Formation of ribosomal protecting protein

GI distress
Enamel dysplasia
Hepatotoxicity
Nephrotoxicity
Photosensitivity
Vestibular toxicity
Teratogenic

Question 4

Tigecycline

Answer 4

Organisms resistant to standard tetracycline
MRSA strains, VRE strains

IV only
Excreted in bile

Pseudomonas and proteu are resistant

GI distress
Enamel dysplasia
Hepatotoxicity
Nephrotoxicity
Photosensitivity
Vestibular toxicity
Teratogenic

Question 5

Tetracycline

CI

Answer 5

Children<10years of age
Pregnancy
Pre-exsiting liver disease