It is a broad-spectrum antibiotic, and its antibacterial spectrum, antibacterial principle and application are basically the same as tetracycline. Many rickettsia, mycoplasma, chlamydia, spirochetes, amoeba and certain plasmodium are also sensitive to this product. Enterococcus is resistant to it. Others such as Actinomyces, Bacillus anthracis, Listeria monocytogenes, Clostridium, Nocardia, Vibrio, Brucella, Campylobacter, Yersinia, etc. are sensitive to this product. This product has certain antibacterial activity against Neisseria gonorrhoeae and meningococcus, but penicillin-resistant Neisseria gonorrhoeae is also resistant to oxytetracycline. Over the years, due to the wide application of tetracyclines, common clinical pathogens are highly resistant to oxytetracycline, including gram-positive bacteria such as staphylococci and most gram-negative bacilli. There is cross-resistance between different varieties of tetracycline antibiotics. The mechanism of action of this product is that the drug can specifically bind to the A position of the 30S subunit of the bacterial ribosome to inhibit the growth of the peptide chain and affect the synthesis of bacterial protein. This product is slightly more effective than tetracycline for intestinal infections, including amoebic dysentery. It has close cross-resistance with tetracycline.