Tetracyclines are a class of broad-spectrum antibiotics used in the management and treatment of a variety of infectious diseases. Naturally occurring drugs in this class are tetracycline, chlortetracycline, oxytetracycline, and demeclocycline. used to treat infections caused by susceptible microorganisms such as gram positive and gram negative bacteria, chlamydiae, mycoplasmata, protozoans, or rickettsiae. please comment thank you [email protected]