Tetracyclines are the first drug of choice for the following EXCEPT
Ans. d (Community acquired pneumonia) (Ref. KDT, Pharmacology, 6th ed., 715)Tetracyclines are 1st choice of drugs for:# Lymphogranuloma venereum # Lyme's disease # Brucellosis # Relapsing feverMneumonic = Lvbra CPG# Rickettsial infection # Atypical pneumonia due to chalmydia # Cholera # Plague prophylaxis # Granuloma inguinale TETRACYCLINESMechanism of actionBacteriostatic; bind to 30S and prevent attachment of aminoacyl-tRNA; limited CNS penetration. Doxycycline is fecally eliminated and can be used in patients with renal failure. Do not take with milk (Ca2+), antacids (Ca2+ or Mg2+), or iron-containing preparations because divalent cations inhibit its absorption in the gut.IndicationsBorrelia burgdorferi, M. pneumoniae. Drug's ability to accumulate intracellularly makes it very effective against Rickettsia and Chlamydia, Also used to treat acne.Advrese effectsGl distress, discoloration of teeth and inhibition of bone growth in children, photosensitivity. Contraindicated in pregnancy.Mech of resistanceuptake or efflux out of bacterial ceils by plasmid-encoded transport pumps. Educational Points# All tetracyclines excreted in urine except--Doxycycline# Contraindicated in pregnancy# Causes fetal tooth enamel dysplasia and bone growth disturbances# Out-dated tetracycline -can cause Fanconi's syndrome & pseudotumor cerebri# Demeclocycline and Doxycycline -Phototoxicity +.# Minocycline -Vestibulotoxicity# Demeclocycline -ADH-like action# Block protein synthesis at 30S ribosomal subunit-Aminoglycosides, tetracyclines.
Granuloma inguinale
Cholera
Atypical pneumonia
Community acquired pneumonia
Anti Microbial