Which one of the following statements about doxycycline is FALSE?: (A) It is bacteriostatic, (B) It is excreted mainly in the feces, (C) It is more active than tetracycline against H.pylori, (D) It is used in Lyme's disease
Answer is C. (Ref: KDT 6/e p637, 710, 712, 713) Doxycycline is a bacteriostatic agent that acts by inhibiting protein synthesis. It is safe in renal failure as it is excreted mainly in feces. Doxycycline is useful in Lyme's disease. Tetracycline (and not doxycycline) is useful in H.pylori therapy.