Tetracycline has a wide range of antibacterial activity. It interferes with the formation of a complex between the transport RNA and the ribosome, which leads to a violation of protein synthesis by a microbial cell. Active in relation to most gram-positive and gram-negative bacteria, spiophets, leptospires, rickettsiaes, trachomae pathogens, ornithosis, and large viruses.

Sumycin - An antibiotic based on tetracycline, a brand of such pharmaceutical companies as Bristol-Myers Squibb, Apothecon, Par Pharmaceutical.