Doxycycline20

Doxycycline is mainly bacteriostatic with a broad spectrum of antimicrobial activity including chlamydia, mycoplasmas, rickettsia, and spirochetes, and aerobic and anaerobic Gram –positive and Gram-negative pathogenic bacteria, and some protozoa. Doxycycline is more active than tetracycline against many bacterial species including enterococci and various anaerobes. Doxycycline reported to be more active against protozoa, particularly Plasmodium spp. Doxycycline taken up into sensitive bacterial cells by an active transport process. Once within the cell they bind reversibly to the 30S subunit of the ribosome, preventing the binding of amino acyl transfer RNA and inhibiting protein synthesis and hence cell growth.